Full Text Available In this paper we studied the energetic expenditure and thermoregulation of the Chilean mouse-opossum Thylamys elegans (Dielphidae a nocturnal small marsupial, endemic of southern South America. We studied their standard energetic and determined whether they exhibit shallow daily torpor or deep prolonged torpor as a function of ambient temperature and food availability. Thylamys elegans partially supports the hypothesis that Neotropical marsupials have somewhat a higher basal metabolic rate (BMR and thermal conductance (Cm than Australian ones. In fact, BMR was higher but Cm was lower than expected for their body mass. The higher mass-independent BMR of the Chilean mouse-opossum may be explained by its insectivorous food habits and its low Cm by its temperate habitats. Euthermic Chilean mouse-opossum showed daily fluctuations in body temperature being significantly higher during night time. In addition T. elegans entered in daily torpor and aroused spontaneously only was food was absent. That is, this species display a facultative type of daily torpor because propensity to enter in torpor was dependent of the combination of food absence and low ambient temperature. No torpor was observed when food was available. During torpor ambient temperature was slightly above ambient temperature between 0.3 to 0.5 °C. Torpor in this species as well as in marsupials in general, appears to be a flexible and an opportunistic response to unpredictable environmental conditionsEstudiamos la energética y termorregulación de Thylamys elegans o "yaca" (Dielphidae un marsupial pequeño y endémico de Sudamérica. Estudiamos su energética estándar y determinamos si presentan estados de sopor superficial o profundo en función de la temperatura ambiente y la disponibilidad de alimento. Thylamys elegans apoya de manera parcial la hipótesis que sostiene que los marsupiales Neotropicales poseen tasas metabólicas basales (BMR y conductancias térmicas (Cm mas altas
Revision de las especies del genero Hyperdidelphys Ameghino, 1904 (Mammalia, Marsupialia, Didelphidae. Su significacion filogenetica, estratigrafica y adaptativa en el neogeno del Cono Sur Sudamericano
Pardiñas, U. F. J.
Full Text Available All species of fossil marsupials belonging to the genus Hyperdidelphys Ameghino, 1904 (Didelphidae, Didelphinae, Didelphini are analyzed and rediagnosed: H. inexpectata (Ameghino, 1889, H. pawula (Rovereto, 1914, H. pattersoni (Reig, 1952 and the new species H. dimartinoi. The biochron of this genus spans from the Late Miocene (Huayquerian StageIAge to the Late Pliocene (Chapadmalalan StageIAge; al1 records referable to species of Hyperdidelphys come from central and northwestern Argentine localities. Hyperdidelphys and Lutreolina conform a monophyletic group among the Didelphini, being Lutreolina the plesiomorphic sister group of Hyperdidelphys. H. pattersoni is the sister group of a clade including two monophyletic groups: H. pawula on one side, and H. inexpectata + H. dimartinoi sp. nov. on the other. Several taxa previously referred to this genus are discussed and excluded from it: (1 Â«Hyperdidelphys brachyodontaÂ» (Reig, 1952 is a junior synonym of Didelphis crucialis Ameghino,1904; (2 Â«Hyperdidelphys biforataÂ» (Ameghino, 1904 is a species of Lutreolina (L. biforata n. comb., and (3 Â«Paradidelphys nodosaÂ» Ameghino, 1904 is a junior synonym of Thylophorops perplana (Ameghino, 1904 n. combo The biostratigraphic significance of the species of Hyperdidelphys in the Late Cenozoic of Southern South America remains unelear: their record in Neogene levels is unfrequent, the identification of two of the four species (H. parvula and H. inexpectata is complex on the basis of known materials, and the biochrones of three of them are not restricted but inelude relatively wide time spans. Carnivorous adaptations of species of Hyperdidelphys correlate with the decline of Sparassodont marsupials in late Miocene-Pliocene times, a process that was previous to the arrival in South America of inmigrant placental carnivores of Holarctic origin by the stablishment of the intercontinental Panamanian land bridge.Se analizan y diagnostican
Ítalo A. Sherlock
Full Text Available An opossum, Didelphis albiventris, from Jacobina, bahia State, was found naturally infected with Leishmania donovani, being the first non-canid wild mammal to be detected with agent of kala-azar in the New World.Um gambá, Didelphis albiventris, de Jacobina, Bahia, foi encontrado com infecção natural pela Leishmania donovani, sendo o primeiro mamífero silvestre não-canídeo a ser achado com o agente do calazar nas Américas.
Hudson Alves Pinto
Full Text Available Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.
Chemisquy, M. Amelia; Martin, Gabriel M.
ABSTRACT Dental anomalies have been investigated and reported for most orders of mammals, including marsupials. Previous works in Didelphis albiventris Lund, 1840 only described one kind of malformation or just a few observations from some collections, thus the type and presence of anomalies for this species was underestimated. The aim of this contribution is to describe and analyze several dental anomalies found in specimens of Didelphis albiventris from Argentina, Uruguay and Brazil. Dental...
M. Amelia Chemisquy
Full Text Available ABSTRACT Dental anomalies have been investigated and reported for most orders of mammals, including marsupials. Previous works in Didelphis albiventris Lund, 1840 only described one kind of malformation or just a few observations from some collections, thus the type and presence of anomalies for this species was underestimated. The aim of this contribution is to describe and analyze several dental anomalies found in specimens of Didelphis albiventris from Argentina, Uruguay and Brazil. Dental anomalies were classified in three categories: supernumerary or missing teeth, morphological anomalies in size and shape, and teeth in unusual positions. We found 32 individuals of D. albiventris with anomalies out of 393 analyzed specimens (8.14%, some specimens with more than one anomaly. A similar proportion of specimens from Argentina and Uruguay presented anomalies, while in specimens from Brazil anomalies were less common. Anomalies were more commonly found in the upper toothrow and in molars, being supernumerary teeth and molars with unusual crown-shape the most common ones. The percentage of specimens with anomalies found for D. albiventris is higher than previously reported for the species, and other Didelphimorphia. Inbreeding and limited gene flow do not appear as possible explanations for the elevated percentage of anomalies, especially due to the ecological characteristics of Didelphis albiventris. Developmental instability and fluctuating asymmetry could be some of the causes for the anomalies found in this species, mostly since the habitat used by D. albiventris tends to be unstable and disturbed. Dental anomalies were mostly found in areas of the toothrow where occlusion is relaxed or does not prevent teeth from interlocking during mastication, and consequently have no functional value.
Atrição dental em Didelphis albiventris e D. marsupialis (Marsupialia, Didelphimorphia, Didelphidae do Sul do Brasil Dental wear in Didelphis albiventris and D. marsupialis (Marsupialia, Didelphimorphia, Didelphidae from southern Brazil
Marília da Silva Aguiar
Full Text Available Pesquisou-se o nível de desgaste dental (atrição e/ou abrasão em 168 espécimes de Didelphis albiventris e D. marsupialis (gambás do sul do Brasil. O desgaste foi muito importante, com elevada freqüência de dentina terciária e de exposição da câmara coronária e/ou do canal radicular, devido à associação de fraturas e desgaste, pois as fraturas predispõem ao desgaste e este favorece as fraturas. O grau de desgaste aumentou com a idade dos animais. A ordem crescente na freqüência de dentina terciária nos dentes caudais aos caninos foi: primeiro, segundo e terceiro molares, terceiro e segundo pré-molar, e quarto molar. Diferentemente de outros onívoros, em Didelphis o desgaste dentário parece mais relacionado às fraturas devidas aos alimentos (seguida de atrição/abrasão do que ao contato entre os dentes. Ao contrário da literatura, os molares tribosfênicos não parecem "ideais" para tal dieta onívora, o que é evidenciado pela elevada freqüência de desgaste, fraturas e exposição da câmara coronária ou do canal radicular.This work deals with the study of dental wear down (atrittion and/or abrasion in 168 specimens of Didelphis albiventris and D. marsupialis from Southern Brazil. Wear down was very important, with high frequency of tertiary dentine and exposition of the pulp cavity/radicular canal, due to the association of fractures and wear down. Fractures predispose wear down which, on the other side, favors fractures. The degree of attrition increased with age. The order of growing frequency of tertiary dentin in poscanines was: first, second and third molars, third and second premolars, and finally fourth molar. Differently from others omnivorous in Didelphis tooth wear down seems rather related to fractures due to food (followed by attrition than to teeth contact. Contrary to literature, tribosphenic molars seems not to be "ideals" for such omnivorous diet, as is evident from the high frequency of wear down, fractures and teeth cavities exposition.
Atrição dental em Didelphis albiventris e D. marsupialis (Marsupialia, Didelphimorphia, Didelphidae) do Sul do Brasil Dental wear in Didelphis albiventris and D. marsupialis (Marsupialia, Didelphimorphia, Didelphidae) from southern Brazil
Marília da Silva Aguiar; Jorge Ferigolo; João Luiz Rossi Junior; Marco Antônio Gioso
Pesquisou-se o nível de desgaste dental (atrição e/ou abrasão) em 168 espécimes de Didelphis albiventris e D. marsupialis (gambás) do sul do Brasil. O desgaste foi muito importante, com elevada freqüência de dentina terciária e de exposição da câmara coronária e/ou do canal radicular, devido à associação de fraturas e desgaste, pois as fraturas predispõem ao desgaste e este favorece as fraturas. O grau de desgaste aumentou com a idade dos animais. A ordem crescente na freqüência de dentina te...
Christopher S. Vaughan
Full Text Available Three Didelphis marsupialis were radio tracked during late dry season (23 February-26 April, 1983 in agricultural area at 1500 m elevation in Central Valley, Costa Rica. All animals were nocturnally active, significantly more so between 2100-0300 h. Fifty diurnal den site locations were found, 96% inside tree cavities in living fence rows or abandoned squirrel nests in windbreaks. Two females occupied 3.4 and 3.1 ha 95% home ranges, moving an average 890 and 686 m nightly respectively. The male occupied a 5.6 ha 95% home range for 42 days overlapping 90% of females' home ranges. Over the next 15 days, he moved 1020 m south, establishing three temporary home ranges. During nocturnal movements, windbreaks and living fence rows were used in higher proportion than available, while pasture, roads and cultivated lands were used less then available within 100% home ranges. Abandoned coffee and spruce plantations, fruit orchards and overgrown pastures were used in equal proportions to availability in 100% home ranges. Opossum conservation techniques in coffee growing areas include promoting spruce windbreaks, living fence rows, and garbage dumps.
Roberta M.P. Humberg
Full Text Available Turgida turgida have been largely reported parasitizing Didelphis species in North and South America based on light microscopy observation. However, the features that differentiate T. turgida from other physalopterid species should be observed using scanning electron microscopy (SEM. A female white-bellied opossum, Didelphis albiventris, arrived dead at the Centro de Reabilitação de Animais Silvestres (CRAS in the municipality of Campo Grande, state of Mato Grosso do Sul, Brazil. During the necropsy, adult nematodes were collected from stomach and intestine. The nematodes were determined to be adult specimens and submitted to SEM for the species determination. This is the first report of T. turgida confirmed by SEM in the Neotropical region and the first report in an urban area in the state of Mato Grosso do Sul, Brazil.
Luis Miguel Lobo
Full Text Available Gracilinanus microtarsus is a small marsupial species belonging to the Didelphidae family. It has an omnivorous/frugivorous feeding habit and, therefore, it has a great ecological importance, because it is a seed-dispersing species. This article aims to describe the macroscopic morphology of the digestive tract in G. microtarsus. We used 4 animals fixed in 10% formaldehyde. The organs were dissected, measured, and photographed. The animals under study had the dental formula 2x I 5/4 C 1/1 P 3/3 M 4/4. This is the dental formula of the whole Didelphidae family. The dorsum of the tongue had vallate, fungiform, and filiform papillae. Tubular esophagus evidenced the cervical, thoracic, and abdominal portions. The unicavitary stomach consisted of glandular and aglandular region and gastric folds. Small intestine had 3 portions: duodenum, jejunum, and ileum. Large intestine consisted of: cecum, colon, and rectum. Parotid salivary gland was the largest and it had a flattened shape. The sublingual salivary gland, whi h was the smallest, had a flattened and elongated shape. Mandibular salivary gland had an oval shape. Pancreas had a dispersed shape and lobulated aspect. Liver had a dome shape and it consisted of the lobes right medial, square, right side, left medial, left side, and caudate. The digestive tract of the animals under study is similar to the marsupial species described in the literature.
Bozinovic, Francisco; Muñoz, José L P; Naya, Daniel E; Cruz-Neto, Ariovaldo P
We studied how food abundance and consumption regulates torpor use and internal organ size in the Chilean mouse-opossum Thylamys elegans (Dielphidae), a small nocturnal marsupial, endemic in southern South America. We predicted that exposure to food rations at or above the minimum energy levels necessary for maintenance would not lead to any signs of torpor, while reducing food supply to energy levels below maintenance would lead to marked increases in frequency, duration and depth of torpor bouts. We also analyzed the relationship between food availability and internal organ mass. We predicted a positive relationship between food availability and internal organ size once the effect of body size is removed. Animals were randomly assigned to one of two groups and fed either 70, 100 or 130% of their daily energy requirement (DER). We found a positive and significant correlation between %DER and body temperature, and also between %DER and minimum body temperature. In contrast, for torpor frequency, duration and depth, we found a significant negative correlation with %DER. Finally, we found a significant positive correlation between the %DER and small intestine and ceacum dry mass. We demonstrate that when food availability is limited, T. elegans has the capacity to reduce their maintenance cost by two different mechanisms, that is, increasing the use of torpor and reducing organ mass.
Carreira João Carlos
through dot blot hybridization using a L. infantum-specific biotinylated probe. Conclusions In the present paper we present the first report of amastigotes in the tissues of Didelphis aurita (Mammalia: Marsupialia naturally infected with Leishmania infantum. We also attempt to claim the particular role of some opossum species as hosts of Leishmania infantum, contributing at least in part on the description of potential sylvatic reservoirs.
Carreira, João Carlos Araujo; da Silva, Alba Valéria Machado; de Pita Pereira, Daniela; Brazil, Reginaldo Peçanha
-specific biotinylated probe. In the present paper we present the first report of amastigotes in the tissues of Didelphis aurita (Mammalia: Marsupialia) naturally infected with Leishmania infantum. We also attempt to claim the particular role of some opossum species as hosts of Leishmania infantum, contributing at least in part on the description of potential sylvatic reservoirs.
Ândrio Zafalon da Silva
Full Text Available Information regarding the similarity of the fauna that colonizes decomposing wildlife is insipient among the different carcass models. Species with different tissues and alimentary diets are hypothesized to be a colonization source of different necrophagous species. To verify this hypothesis, we observed the decomposition of a carcass of Didelphis albiventris Lund, 1841 (Didelphimorphia, Didelphidae, that had been run over by a vehicle. 2,273 adults were reared from specimens at immature stages collected on the carcass. The most representative species belongs to Calliphoridae, Muscidae, Sarcophagidae and Fanniidae, with numeric dominance of Lucilia eximia Wiedemann, 1819 (Diptera, Calliphoridae. Another six species were found, besides non-identified Fanniidae specimens. All species were colonizers of traditionally used forensic models.
Luis Miguel Lobo
Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n1p109 Gracilinanus microtarsus é um pequeno marsupial pertencente à família Didelphidae. Possui hábito alimentar onívoro/frugívoro sendo, portanto, uma espécie de grande importância ecológica, por ser dispersora de sementes. O objetivo deste estudo é descrever a morfologia macroscópica do aparelho digestório do G. microtarsus. Foram utilizados quatro animais fixados em formaldeído 10%. Os órgãos foram dissecados, mensurados e fotografados. Os animais estudados apresentaram a fórmula dentária 2x I 5/4 C1/1 P 3/3 M 4/4. Esta é a fórmula dentária de toda a família Didelphidae. O dorso da língua apresentou papilas valadas, fungiformes e filiformes. O esôfago tubular revelou as porções cervical, torácica e abdominal. O estômago monocavitário era composto por região glandular e aglandular e pregas gástricas. O intestino delgado apresentou três porções: duodeno, jejuno e íleo. O intestino grosso era composto por: ceco, cólon e reto. A glândula salivar parótida era a maior e apresentava formato achatado. A glândula salivar sublingual, que era a menor, apresentava formato achatado e alongado. A glândula salivar mandibular apresentava formato ovalado. O pâncreas apresentou forma dispersa e aspecto lobulado. O fígado apresentava formato de cúpula e era composto pelos lobos medial direito, quadrado, lateral direito, medial esquerdo, lateral esquerdo e caudado. O aparelho digestório dos animais estudados é semelhante ao de marsupiais descritos na literatura.
Carolina Bezerra Silva, Ana
A evolução do dimorfismo sexual de forma e tamanho do crânio e mandíbula foi estudada em 31 táxons de marsupiais didelfídeos, a fim de compreender melhor o desenvolvimento desse caráter na família. Para elucidar fatores que poderiam estar condicionando esse dimorfismo nos Didelphidae, foi analisada também a evolução de outros dois elementos: alometrias entre tamanho e forma do crânio e da mandíbula; e bionomia das mesmas 31 espécies. Foi realizado um mapeamento de todos estes caracteres, qual...
Núbia P. Pereira
Full Text Available The karyotypes of 23 specimens belonging to 16 species from nine genera of Brazilian marsupials (family Didelphidae were studied. The animals were collected in eight localities of Cerrado or Atlantic Forest biomes in the states of Goiás, Tocantins and São Paulo. The karyotypes were analyzed after conventional Giemsa staining and silver staining of the nucleolus organizer regions (Ag-NORs. New karyotypic data were obtained for Gracilinanus microtarsus (2n = 14, FN = 24, Marmosops paulensis (2n = 14, FN = 24 , Micoreus paraguayanus (2n = 14, FN = 20 and Monodelphis rubida (2n = 18, FN = 32 and are discussed in detail. The karyotypes of G. microtarsus , M. paulensis and M. paraguayanus include three large pairs of submetacentrics (pairs 1, 2 and 3 and a medium-sized metacentric or submetacentric pair 4. Pairs 5 and 6 are small submetacentrics in G. microtarsus and M. paulensis and acrocentrics in M. paraguayanus . M. paulensis presented a single Ag-NOR in pair 6 (6p6p, while M. paraguayanus exhibited multiple Ag-NORs in pairs 5 and 6 (5pq5pq6p6p. There was variation in size and morphology of the sex chromosomes among these species. Monodelphis rubida presented a karyotype with 2n = 18 and FN = 32 composed of a large submetacentric pair 1, a medium-sized metacentric pair 2 and six pairs of submetacentrics (pairs 3 through 8. The X was a small acrocentric and the Y was dot-like. A single Ag-NOR bearing pair (5p5p characterized M. rubida. Relevant karyotypic information was obtained for 19 specimens belonging to 12 species collected in areas sampled for the first time [ Caluromys lanatus and C. philander (2n = 14, FN = 20, Gracilinanus emiliae (2n = 14, FN = 24, Marmosa murina , Metachirus nudicaudatus and Micoureus demerarae (2n = 14, FN = 20, Monodelphis americana (2n = 18, FN = 32 and M. domestica (2n = 18, FN = 20, and Didelphis marsupialis, Philander frenata, P. opossum and P. sp (2n = 22, FN = 20]. Although the karyotypes were relatively
Cáceres Nilton Carlos
Full Text Available Use of the space by the opossum Didelphis aurita Wied-Newied, 1826 (Mammalia, Marsupialia in a mixed forest fragment of southern Brazil. The space use of the marsupial Didelphis aurita was studied in a forest fragment of southern Brazil from February 1995 to January 1996. The method used was the 'distribution utilization' in which each trap was set in 38 x 38 m quadrats. Captures of each marked individual in each point give information on its habitat use. Food availability was searched and compared to the habitat utilization and to the food consumption of opossums. Distribution patterns of captures (aggregated to random and spatial overlap between individuals were searched. Results showed aggregated distributions of individuals, particularly females, in the fragment. Females used exclusively the fragment during the drier season. Opossums tend to not choose the sites with highest food availability to establish home ranges. Spatial overlap was usually low between forest resident and neighbouring resident females, but much lower during the breeding season (only forest resident females in an apparently pattern of territoriality. Hence, core areas of females decreased in size during the breeding season. Males probably searched primarily for mates during the breeding season being less opportunistic than females in feeding habits, yet their space use did not correlate to food consumption.
Ortiz, P. E.; Teta, P.
A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP) from Inca Cueva 5 site (23" 05' S - 65" 27' W; 3700 m.a.s.l., Jujuy Province, Argentina) was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Fam...
Vanessa Abelaira dos Anjos
Full Text Available http://dx.doi.org/10.5007/2175-7925.2010v23n2p211 As informações relativas quanto à similaridade da fauna colonizadora de animais silvestres em decomposição são incipientes entre os diferentes modelos de carcaças. É esperado que espécies que possuam tecidos e dietas alimentares diferentes ao morrerem sejam fontes de colonização de diferentes espécies necrófagas. Para a verificação desta hipótese foi acompanhada a decomposição de uma carcaça de Didelphis albiventris Lund, 1841 (Didelphimorphia, Didelphidae, encontrado morto por atropelamento. Foram criados 2.273 adultos a partir de imaturos coletados na carcaça, representados por espécies pertencentes á Calliphoridae, Muscidae, Sarcophagidae e Fanniidae, com dominância numérica de Lucilia eximia Wiedemann, 1819 (Diptera, Calliphoridae. Outras seis espécies foram encontradas junto de espécimes não identificados de Fanniidae. Todas as espécies encontradas são colonizadoras de modelos tradicionalmente utilizados para estudos de Entomologia Forense.
Casartelli, C; Rogatto, S R; Ferrari, I
Three species of marsupials from the Amazon region (Marmosa cinerea, Caluromys lanatus, and Didelphis marsupialis) and two from the region of São Paulo (Didelphis marsupialis and Didelphis albiventris) were studied. The G-banding pattern of the species with 2n = 14 (M. cinerea and C. lanatus......, being located in the telomeric region of one pair and in the centromeric region of the other pair. Caluromys lanatus has centromeric Ag-NORs in one acrocentric and in one submetacentric chromosome pairs. Didelphis marsupialis has three chromosome pairs with telomeric Ag-NORs. In D. albiventris the Ag......) was very similar, as well as the pattern of G-bands in the species with 22 chromosomes (Didelphis). All of the autosomes of M. cinerea and D. albiventris have centromeric C-bands and the Y chromosome is totally C-band positive. The long arm of the M. cinerea X chromosome is completely C-band positive...
Díaz, M. Mónica
Se presenta el resultado de un estudio realizado en la localidad de Iquitos y sus alrededores, un área ubicada en la Amazonía del noreste de Perú. Se ofrece una lista de especies de marsupiales registrados mediante colectas realizadas personalmente, información obtenida de la literatura, y registros confiables. Para cada especie se mencionan las localidades de colecta y presentan comentarios sobre su sistemática e historia natural. Se citan 19 especies para Iquitos, 14 fueron colectadas en...
Acosta-Virgen, Karla; López-Caballero, Jorge; García-Prieto, Luis; Mata-López, Rosario
Abstract From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum) were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes). Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals. PMID:26257556
Full Text Available From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes. Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals.
Sharon A Jansa
Full Text Available The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae and pitvipers (Serpentes: Crotalinae. In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF, a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role.
Hogan, Lindsay A; Janssen, Tina; Johnston, Stephen D
This review provides an update on what is currently known about wombat reproductive biology and reports on attempts made to manipulate and/or enhance wombat reproduction as part of the development of artificial reproductive technology (ART) in this taxon. Over the last decade, the logistical difficulties associated with monitoring a nocturnal and semi-fossorial species have largely been overcome, enabling new features of wombat physiology and behaviour to be elucidated. Despite this progress, captive propagation rates are still poor and there are areas of wombat reproductive biology that still require attention, e.g. further characterisation of the oestrous cycle and oestrus. Numerous advances in the use of ART have also been recently developed in the Vombatidae but despite this research, practical methods of manipulating wombat reproduction for the purposes of obtaining research material or for artificial breeding are not yet available. Improvement of the propagation, genetic diversity and management of wombat populations requires a thorough understanding of Vombatidae reproduction. While semen collection and cryopreservation in wombats is fairly straightforward there is currently an inability to detect, induce or synchronise oestrus/ovulation and this is an impeding progress in the development of artificial insemination in this taxon.
Tomlinson, Sean; Withers, Philip C; Maloney, Shane K
We describe how behavioural responses are an important adjunct to physiological responses for two dunnart marsupials that live in arid environments. Behavioural responses of the stripe-faced dunnart Sminthopsis macroura and the Ooldea dunnart Sminthopsis ooldea differed with acclimation to four ambient temperature (T(a)) regimes, 12 h:12 h of 5-15 °C, 12-22 °C, 18-28 °C and 25-35 °C. Aggression levels were low at regimes 5-15 °C and 12-22 °C, and high at regimes 18-28 °C and 25-35 °C. The proportion of S. macroura huddled in groups increased significantly with decreasing T(a) regime, but there was no aggregation by S. ooldea at low T(a) regimes. The energetic benefit of huddling by S. macroura was highest for pairs of dunnarts (27% saving compared with singles) and only 3% for triplets at T(a)=10 °C. Thermal conductance decreased for pairs but not triplets compared to singles. There were no energetic savings for S. ooldea with increased numbers, and thermal conductance was the same per individual for single, pairs and triplets, reflecting their lack of huddling behaviour. The flexible behavioural (huddling) responses of S. macroura may facilitate their capacity to occupy a broad geographical distribution, unlike S. ooldea, which had inflexible behavioural responses (no huddling) and has a more restricted geographical range. The phylogenetic relationships of the dunnarts suggest that social behaviours may have arisen only once in the most adaptable subgroup of the Sminthopsini. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.
Manoel do Carmo P. Soares
Full Text Available Anti-HAV was detected by enzyme - immunoassay in sera collected from 6 (18,75% of 32 Didelphis marsupialis trapped in the Amazon region. No anti-HAV were found in the sera from 136 other wild animals, including small rodents, reptiles and other marsupials.
Warburton, Natalie Marina
The jaw muscles were studied in seven genera of macropodoid marsupials with diets ranging from mainly fungi in Potorous to grass in Macropus. Relative size, attachments, and lamination within the jaw adductor muscles varied between macropodoid species. Among macropodine species, the jaw adductor muscle proportions vary with feeding type. The relative mass of the masseter is roughly consistent, but grazers and mixed-feeders (Macropus and Lagostrophus) had relatively larger medial pterygoids and smaller temporalis muscles than the browsers (Dendrolagus, Dorcopsulus, and Setonix). Grazing macropods show similar jaw muscle proportions to "ungulate-grinding" type placental mammals. The internal architecture of the jaw muscles also varies between grazing and browsing macropods, most significantly, the anatomy of the medial pterygoid muscle. Potoroines have distinctly different jaw muscle proportions to macropodines. The masseter muscle group, in particular, the superficial masseter is enlarged, while the temporalis group is relatively reduced. Lagostrophus fasciatus is anatomically distinct from other macropods with respect to its masticatory muscle anatomy, including enlarged superficial medial pterygoid and deep temporalis muscles, an anteriorly inflected masseteric process, and the shape of the mandibular condyle. The enlarged triangular pterygoid process of the sphenoid bone, in particular, is distinctive of Lagsotrophus. (c) 2009 Wiley-Liss, Inc.
Ortiz, P. E.
Full Text Available A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP from Inca Cueva 5 site (23" 05' S - 65" 27' W; 3700 m.a.s.l., Jujuy Province, Argentina was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Family Abrocomidae, Abrocoma cinerea; Family Chinchillidae, Lagidium viscacia; Family Octodontidae, Octodontomys gliroides. The taphonomy indicates that the sequence is an owl pellet accumulation inside the cave. The general landscape corresponds to the oriental border of the Puna steppe, with scattered shrub and low brush vegetation. Near the site there are small tree groups of Polylepis australis as well as small streams covered with grass and ciperaceous vegetation known as Â«vegasÂ». Al1 the recorded taxa at Inca Cueva 5 exist today in Puna and Prepuna environments from Jujuy and Salta Provinces and southem Bolivia, excepting Cavia cf. C. tschudii. The modem records of this species in northem Argentina and southern Bolivia come from localities with high montane bunchgrass prairies and forests of the humid Yungas phytogeographical region. The presence of this species in the sequence suggests wetter climatic conditions on this region when the archaeological site was originated. Later drier conditions, caused probably by anthropic influence in the last 500 years, produced the retraction of Cavia tschudii to the moist eastern side of the Andes and its disappeareance of the Puna areas.El sitio arqueológico Inca Cueva 5 se encuentra en la provincia de Jujuy, Argentina, en el borde oriental de la región de la Puna (23" 05' S - 65" 27' W; 3700 m s n m y está fechado entre 2120 f 120 y 780 f 100 años radiocarbónicos AP. El estudio de una pequeña muestra de
Monet-Mendoza, Anne; Osorio-Sarabia, David; García-Prieto, Luis
The goal of this study was to provide further information about helminth parasites of Virginia opossum Didelphis virginiana Kerr, 1792 from Mexico. During routine faunal investigations between 1958 and 2001, 101 opossum were necropsied. Nineteen taxa of helminths were collected, representing 13 genera from hosts in 27 localities from Mexico. There are 58 new locality records, with 6 species recorded in Mexico for the first time: Brachylaima virginiana Dickerson, 1930; Cruzia americana Mapleston, 1930; Didelphonema longispiculata (Hill, 1939); Didelphostrongylus hayesi Prestwood, 1976; Viannaia didelphis Travassos, 1914; and Viannaia viannai Travassos, 1914. This increases the number of helminth taxa previously known for this host in Mexico to 28.
Full Text Available Trypanosoma (Megatrypanum saloboense n. sp., is described in the Brazilian opossum Monodelphis emiliae (Thomas, 1912 from primary forest in the Salobo area of the Serra dos Carajás (6° S, 50° 18′ W Pará State, North Brazil. Two morphologically different trypomastigotes were noted. Slender forms, regarded as immature parasites, have a poorly developed undulating membrane adhering closely to the body: large, broad forms with a well developed membrane are considered to be the mature trypomastigotes and have a mean total length of 71.2 μm (62.4-76.2 and a width of 6.1 (5.0-8.0. Infections studied in two opossums were of very low parasitaemia. The large size of T. (M. saloboense readily distinguishes it from the two previously described members of the subgenus Megatrypanum of neotropical marsupials, T. (M. freitasi Régo et al., 1957 of Didelphis azarae and D. marsupialis, and T. (M. samueli Mello, 1977 of Monodelphis domesticus, which measure only 49.0-51.5 μm and 42.4 μm respectively. No infections were obtained in hamsters inoculated with triturated liver and spleen from one infected M. emiliae, or in laboratory mice inoculated with epimastigotes from a blood-agar culture. No division stages could be detected in the internal organs or the peripheral blood.
Carlos Eduardo Faresin e Silva
Full Text Available We investigated the karyotype of 18 didelphid species captured at 13 localities in the Brazilian Amazon, after conventional staining, C-banding, Ag-NOR and fluorescent in situ hybridization (FISH using the 18S rDNA probe. Variations were found in the X chromosome, heterochromatin distribution and the 18S rDNA sequence. The main variation observed was in the position of the centromere in the X chromosome of Caluromys philander Linnaeus, 1758 and Marmosa murina Linnaeus, 1758. For both species, the X chromosome showed a geographical segregation in the pattern of variation between eastern and western Brazil, with a possible contact area in the central Amazon. C-banding on the X chromosome revealed two patterns for the species of Marmosops Matschie, 1916, apparently without geographic or specific relationships. The nucleolus organizer region (NOR of all species was confirmed with the 18S rDNA probe, except on the Y chromosome of Monodelphis touan Shaw, 1800. The distribution of this marker varied only in the genus Marmosa Gray, 1821 [M. murina Thomas, 1905 and M. demerarae Thomas, 1905]. Considering that simple NORs are seen as a plesiomorphic character, we conclude that the species Marmosa spp. and Didelphis marsupialis Linnaeus, 1758 evolved independently to the multiple condition. By increasing the sample, using chromosomal banding, and FISH, we verified that marsupials present intra- and interspecific chromosomal variations, which suggests the occurrence of frequent chromosomal rearrangements in the evolution of this group. This observation contrasts with the chromosomal conservatism expected for didelphids.
Use of space by neotropical marsupial Didelphis albiventris (Didelphimorphia: Didelphidae in an urban forest fragment Uso do espaço pelo marsupial Neotropical Didelphis albiventris (Didelphimorphia: Didelphidae em um fragmento florestal urbano
Alex J. de Almeida
Full Text Available A population of the Neotropical marsupial Didelphis albiventris (Lund, 1840 living in an urban forest fragment was studied. Population structure and the influence of sex and age on two variables related to habitat use (Daily home range - MCP and Habitat use intensity - UI obtained by the spool-and-line technique were analysed. There were 20 males and 29 females studied (N = 49. No sexual dimorphism was apparent in adult individuals. There were 16 males and 24 females tracked using the spool-and-line device. There were significant differences found in the mean size of the daily home range, which was greater in adults than in sub-adults. Regarding the habitat use intensity there were also significant differences related to age. There were no significant differences in MCP and UI related to the sex of the individuals. Besides the analyzed factors, the variables related to habitat use are possibly influenced by other factors, especially, the ones related to the conservation status of the fragment.Neste estudo foi analisada uma população do marsupial neotropical Didelphis albiventris (Lund, 1840, em um fragmento florestal urbano, e foram analisados aspectos da estrutura da população, e a influência do sexo e da idade em duas variáveis relativas ao uso do hábitat - Área de Vida Diária (MCP e Intensidade de Uso do Hábitat (UI, obtidas com a técnica do carretel de rastreamento. Foram estudados 49 indivíduos marcados, dos quais 20 eram machos e 29 eram fêmeas. Dos animais adultos, não foi encontrado qualquer dimorfismo sexual. De 40 indivíduos rastreados com carretel (16 machos, 24 fêmeas, diferenças significativas no MCP foram encontradas, sendo que os indivíduos adultos apresentaram tamanhos médios maiores que os sub-adultos. Quanto à UI, diferenças significativas foram observadas também relacionadas à idade. Não foram encontradas diferenças entre sexos com relação ao MCP e IU. Além dos fatores analisados, as variáveis relativas ao uso do hábitat possivelmente são influenciadas por outros fatores, especialmente aqueles relacionados ao estado de conservação do fragmento.
Torres-Montoya, E H; Zazueta-Moreno, J M; Osuna-Martínez, L U; Castillo-Ureta, H; Silva-Hidalgo, G; López-Moreno, H S; Osuna-Ramírez, I; Noguera-Corona, E; Rendón-Maldonado, J G
Gnathostoma turgidum is a nematode parasite that exploits the stomach of Virginian opossums, Didelphis virginiana, in Latin America. The opossum is the definitive host of G. turgidum in the wild. Intrahepatic growth and maturation of the parasite, subsequent migration to the stomach and spontaneous expulsion are common. However, the histopathological lesions caused by G. turgidum are poorly described. A better understanding of the life cycle of this parasite and the pathological changes in natural host-parasite interactions could help to clarify the progression of human infections caused by Gnathostoma binucleatum. The aim of this work was to study morphological changes in the liver and stomach of D. virginiana during natural infection and adult worm expulsion. Three opossums naturally infected with G. turgidum were captured from an endemic area of gnathostomosis. Three uninfected opossums captured from a non-endemic area were used as controls. The opossums were sacrificed at different stages of infection (March, May and December), and a histopathological study of their livers and stomachs was conducted. Injuries in livers were observed by histopathology - areas of necrosis and collagen septa were identified. Parasites caused nodules with necrosis on the periphery of lesions, and collagen fibres were also observed in stomachs. Collagen septa may be caused by antigenic remains of the parasite. Further immunological studies are necessary to verify that stimulation is caused by these factors.
Patricia Villa Nova
Full Text Available The present study acknowledges the diversity of fossil marsupials from the Gruta dos Moura cave, as well as environmental and climatic aspects during the Quaternary. The results show that this is the largest diversity of Pleistocene marsupials recorded in a single cave: Didelphis albiventris, D. aurita, Gracilinanus agilis, G. microtarsus, Marmosa murina, Monodelphis brevicaudata, M. domesticaand Sairadelphys tocantinensis. Furthermore, the described specimens are also part of the only fossil assemblage unequivocally referable to the late Pleistocene. Paleontological studies suggest an intimate association with dry and open environments with high abundance of water sources. Since most of the identified taxa are characteristic of open forests and gallery forests, this could represent the actual environment around the Gruta dos Moura cave. Recent studies identified sympatric occurrences between species from open and dry environments and species from humid forests that were identified among our material and are characteristic of humid regions. Therefore, these species could inhabit gallery forests and capons, or even ecotones, inside a dry and open environment. Moreover, the extinction of Sairadelphyscould also indicate that the climatic and environmental conditions changed or that the past environment was more heterogeneous than the current environment of the region.
Full Text Available The body size of vertebrates isolated on islands can undergo changes due to ecological features of these environments. This study aimed to compare the body size of the common opossum, Didelphis aurita, from different insular populations within the same archipelago in southern Brazil. The opossum populations showed corporal variation and different hypotheses were raised to understand the results. This study constitutes the most detailed body size comparison of a marsupial within different insular populations in the Neotropical zone and the data gathered represents an initial contribution for regional fauna biometric knowledge.
Nilton Carlos Cáceres
Full Text Available A two year study of dung beetles and ants acting on scats of two species of opossum (Didelphis spp. was carried out. Scats were left in the field in order to detect post-dispersal agents. A portion of each scat (30 % was examined for seeds in the laboratory. Beetles were recovered from burrows (51 % of 84 faecal samples left in the field where they either buried scats of opossums or were attracted, together with ants, to pitfalls (N= 10 baited with opossum scats. Dung beetles were the main post-dispersal agents of seeds found in scats of opossums, rolling the scats away or burying then on the site of deposition. They buried faeces at 4 to 15 cm in depth (N= 22 tunnels. The main dung beetles identified (medium to large size were Eurysternus (28.7 % in pitfalls and Dichotomius (13.7 %, Coprophanaeus (seen only directly on faeces, besides small-bodied beetles (Por dos años estudiamos los escarabajos coprófagos y las hormigas que actúan en las heces de zarigüellas (Didelphis. Se dejaron excrementos en el campo para descubrir los agentes secundarios de dispersión. Una parte de cada excremento (30 % fue analizada en laboratorio para estimar el número de semillas. Se recolectaron escarabajos del suelo (51 % de 84 excrementos dejados en el campo. También capturamos escarabajos y hormigas con trampas (N= 10. Los escarabajos coprófagos son los principales agentes secundarios de dispersión. Ruedan los excrementos o los entierran a 4-15 cm de profundidad (N= 22 túneles. Los escarabajos coprófagos de mayor tamaño fueron Eurysternus cyanescens (28.7 % en trampas, Dichotomius assifer (13.7 % y Coprophanaeus saphirinus (sólo visto en madrigueras y directamente sobre los excrementos. Los escarabajos de menos de 10 mm fueron el 57.6 %. La hormiga Acromirmex sp. fue 25.5 % del total de hormigas capturadas en trampas. Hallamos varias especies de semillas en los excrementos, muchos de ellos enterrados por los escarabajos, y algunas fueron extraídas por las hormigas. Estos agentes secundarios ayudan a evitar los depredadores de semillas (eg. roedores y aceleran la formación del banco de semillas, pues no las comen
Abstract. In May 2009 were collected 18 larvae of Lucilia eximia (Wiedemann, a fly responsible for primary and secondary myiasis in livestock and humans. The larvae were taken from the myiasis on anal and auricular regions of an opossum Didelphis albiventris (Lund, in Brasília Zoo, and later identified in the laboratory. After 15 days, 15 adults emerged from L. eximia. This is the first record of this blowfly causing a primary myiasis in a marsupial species in the Brasília Cerrado.
Punzo, F; Farmer, C
Studies were conducted to assess the spatial learning ability in adult males of the short-tailed opossum, Monodelphis domestica using a T-maze, complex maze and elevated radial 8-arm maze. This is the first study of maze learning in opossums. In the T-maze, the performance of these animals improved over an 8-day training period. Eighty percent of the subjects initially trained to turn to the right for food reinforcement reached criterion (80% correct responses) by day 3 and all reached criterion by day 4. Reversal training (subjects then trained to turn to the left) was more difficult and required 8 days for all subjects to reach criterion. In the complex maze, 89% of the animals achieved the criterion level of performance (3 consecutive trials with 5 or fewer errors) on the eighth day of training and all reached criterion by day 10. The relative importance of intramaze vs. extramaze cues in directing choice behavior was investigated in the radial arm maze. A discrimination procedure was used which selectively rewarded subjects for following only one set of cues. Animals in the intramaze group obtained a food pellet from a cup at the end of each arm. In the extramaze group, the food cups were placed on a small platform just beyond the end of each arm. All subjects were initially trained to visit each arm with the maze in a fixed position (controls) and did so within 15 test sessions. Following these initial trials, the maze was rotated to a different position after each choice. For subjects in the intramaze group, the food moved in conjunction with the rotation of the arms thereby increasing the relevance of intramaze cues. In the extramaze group, extramaze cues became more important because the food remained on the platforms in the same position in the room. Animals in the extramaze group performed significantly better than chance whereas the intramaze subjects did not. This indicates that intramaze cues are not as important as extramaze cues for accurate choice behavior in this marsupial. In addition, animals injected with tetraethyllead showed a significant impairment in running speed and T-maze learning ability as compared to saline-injected controls.
Full Text Available Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp. in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.
O'Neill, R J; Eldridge, M D; Toder, R; Ferguson-Smith, M A; O'Brien, P C; Graves, J A
Marsupial mammals show extraordinary karyotype stability, with 2n = 14 considered ancestral. However, macropodid marsupials (kangaroos and wallabies) exhibit a considerable variety of karyotypes, with a hypothesised ancestral karyotype of 2n = 22. Speciation and karyotypic diversity in rock wallabies (Petrogale) is exceptional. We used cross species chromosome painting to examine the chromosome evolution between the tammar wallaby (2n = 16) and three 2n = 22 rock wallaby species groups with the putative ancestral karyotype. Hybridization of chromosome paints prepared from flow sorted chromosomes of the tammar wallaby to Petrogale spp., showed that this ancestral karyotype is largely conserved among 2n = 22 rock wallaby species, and confirmed the identity of ancestral chromosomes which fused to produce the bi-armed chromosomes of the 2n = 16 tammar wallaby. These results illustrate the fission-fusion process of karyotype evolution characteristic of the kangaroo group.
Ortiz Jaureguizar, E.
Full Text Available The extinct subfamily Pichipilinae is a monophyletic group that comprise three genera and six species of small marsupials that lived on Southern South America from early Colhuehuapian (early Miocene to Montehermosan (late Pliocene land-mammal Â«agesÂ». A cladistic analysis of the Pichipilinae was carried out using sixteen dental characters, and the six species considered as terminal taxa. Apomorphic character states were identified using the subfamily Caenolestinae as outgroup. The analysis yielded one cladogram, with 16 steps, a consistency index of 0.93, and a retention index of 0.83. In this cladogram: 1 Phonocdromus gracilis is the sister group to the other Pichipilinae species; 2 Pichipilus halleuxi + Pliolestes tripotamicus and Pichipilus rigssi + Pichipilus centinelus + Pichipilus osborni are two sistergroups, and 3 the relationship among Pichipilus rigssi + Pichipilus centinelus + Pichipilus osborni is unresolved. The results of the cladistic analysis support the previous hypothesis of a close phylogenetic relation between Pliolestes tripotamicus and Pichipilus halleuxi. It is probably that new and more complete fossil specimens of Pichipilus halleuxi allow: a to include this species in Pliolestes; or b to include Pliolestes tripotamicus in Pichipilus. It is possible to infer that Pichipilinae were scansorial, nocturnal and insectivorous- frugivorous mammals, that lived on wet and warm-temperate climatic conditions. Probably, its extinction was related to the climatic-environmental changes occurred on Southern South America during the middle Miocene-late Pliocene span.La subfamilia Pichipilinae es un grupo monofilético que comprende tres géneros y seis especies de pequeños marsupiales extinguidos, que habitaron el extremo austral de América del Sur desde la Â«Edad-mamíferoÂ» Colhuehuapense (Mioceno temprano hasta la Montehermosense (Plioceno tardío. Se realizó un análisis cladístico de los Pichipilinae empleando dieciséis caracteres dentales, y las seis especies conocidas fueron consideradas como taxones terminales. Los caracteres apomórficos fueron identificados utilizando a la subfamilia Caenolestinae como grupo externo. El análisis produjo un cladograma, con 16 pasos, un índice de consistencia de 0,93 y un índice de retención de 0,83. En este cladograma: 1 Phonocdromus gracilis es el grupo hermano de las restantes especies de Pichipilinae; 2 Pichipilus halleuxi + Pliolestes tripotamicus y Pichipilus rigssi + Pichipilus centinelus + Pichipilus osborni son dos grupos hermanos y 3 la relación entre Pichipilus rigssi + Pichipilus centinelus + Pichipilus osborni no está resuelta. Los resultados del análisis cladístico soportan la hipótesis previa de una estrecha relación filogenética entre Pliolestes tripotamicus y Pichipilus halleuxi. Es posible que nuevos y más completos especímenes fósiles de Pichipilus halleuxi permitan: a incluir esta especie en Pliolestes; o b incluir a Pliolestes tripotamicus en Pichipilus. Es posible inferir que los Pichipilinae fueron mamíferos escansoriales e insectívoro-frugívoros, que vivieron bajo condiciones climático-ambientales húmedas y templado-cálidas. La extinción de estos marsupiales estuvo relacionada probablemente con los cambios climático-ambientales ocurridos en la porción austral de América del Sur durante el lapso Mioceno medio-Plioceno.
Full Text Available A new cephalobaenid pentastome, Rileyella petauri gen. nov., sp. nov. from the lungs and nasal sinus of the petaurid marsupial, Petaurus breviceps, is described. It is the smallest adult pentastome known to date, represents the first record of a mammal as the definitive host of a cephalobaenid and may respresent the only pentastome known to inhabit the lungs of a mammal through all its instars, with the exception of patent females. Adult males, non-gravid females and nymphs moulting to adults occur in the lungs; gravid females occur in the nasal sinus. R. petauri is minute and possesses morphological features primarily of the Cephalobaenida but the glands in the cephalothorax and the morphology of the copulatory spicules are similar to some members of the remaining pentastomid order, the Porocephalida. This unusual combination of features distinguish the new genus from other genera in the Cephalobaenida. The occurrence of only seven fully-formed larvae in eggs in the uterus, each representing about 10 % of the length of the patent female, and her presence in the nasal sinus of a dependent juvenile P. breviceps (36 gm implies a direct life cycle.
Ueck, M.; Hoefner, A.J.
In Dasyurus hallucatus the subcommissural organ (SCO) cells differentiate around the 22nd day after gestation (a.g.). 3 H-thymidine studies demonstrate no multiplication of differentiated SCO cells. The cells of the lateral part of the organ multiply longer than the cells of the medial part. Beside the secretion into the cerebrospinal fluid, the subcommissural organ cells possess intimate contact with their basal processes to leptomeningeal blood vessels. Between the 40th and 100th day a.g., but not in adults, a concentration of cells like the tail of a comet is demonstrated in the dorsomedian wall of the aquaeduct of Sylvii. (author)
Reproductive effort and seasonality associated with male-biased parasitism in Gracilinanus agilis (Didelphimorphia: Didelphidae) infected by Eimeria spp. (Apicomplexa: Eimeriidae) in the Brazilian cerrado.
Strona, A L S; Levenhagem, M; Leiner, N O
The aggregation of parasites among hosts is associated with differential host exposure and susceptibility to parasites, which varies according to host gender, body size, reproductive status and environmental factors. We evaluated the role of these factors on infestation by Eimeria spp. (Eimeriidae) in the agile gracile mouse opossum (Gracilinanus agilis), a semelparous didelphid inhabiting neotropical savannahs. Eimeria spp. abundance and prevalence among G. agilis were associated with the breeding status of individuals and to a lesser extent to climatic season, with both sexes presenting higher Eimeria spp. burdens during late breeding/wet season. On the other hand, male-biased parasitism was restricted to dry/mating season. We suggest that male spatial organization and diet may account for increased parasite burdens within this sex, although future studies should evaluate the role of physiological differences associated with androgen hormones. Finally, a rapid increase in Eimeria spp. loads among females during the late breeding/wet season seems associated with seasonal changes in susceptibility, due to breeding costs related to semelparity, and exposure to infective propagules, while male-die off seems to explain maintenance of higher Eimeria spp. burdens within this sex in the same period.
Edsel Amorim Moraes Junior
Full Text Available From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905 (three males and four females were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points, and minimum convex polygon (MCP methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100% ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95% were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night than females (335.1 m/night (t test, t = 3.609, p = 0.001. We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less. Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817.No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905 (três machos e quatro fêmeas foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações e polígono mínimo convexo (PMC, com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100% variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95% foram 4-10,9 ha para machos e 1,3-5,9 ha para fêmeas. Os animais locomoveram em média 423 m/noite, com machos se deslocando mais (582,8 m/noite que as fêmeas (335,1 m/noite (Teste t; t = 3,609; p = 0,001. Concluímos que o rádio rastreamento proporcionou áreas de uso superiores ao de estudos tradicionais realizados com capturas em armadilhas, sugerindo que pode haver uma subestimativa quando a área coberta com armadilhas é relativamente pequena (1 ha ou menos. O rádio-rastreamento também indicou que M. demerarae, embora seja predominantemente arborícola e pesa cerca de 130 g, possui movimentos semelhantes em magnitude a marsupiais terrestres de maior porte, como Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817.
Prevalence of larvae of the bot fly Cuterebra simulans (Diptera, Oestridae on Gracilinanus microtarsus (Didelphimorphia, Didelphidae in southeastern Cerrado from Brazil Prevalência de parasitismo de larvas de Cuterebra simulans (Diptera, Oestridae em Gracilinanus microtarsus (Didelphimorphia, Didelphidae no Cerrado do sudeste do Brasil
Leonardo Dominici Cruz
Full Text Available The prevalence of Cuterebra simulans bot fly parasitism on marsupial Gracilinanus microtarsus was compared between sexes and seasons of the year. No significant difference was observed between females and males but prevalence was higher in warm-wet season than cool-dry season. This pattern agree with observations of others studies with oestrids flies in southern Neotropical areas, suggesting the occurrence of latitudinal change in the peak of bot flies reproductive activity related to seasons of the year along these systems. This is the first record of C. simulans larvae parasitism on G. microtarsus and its occurrence in southern areas of the Neotropical region.A prevalência de parasitismo das larvas da mosca Cuterebra simulans no marsupial Gracilinanus microtarsus foi comparada entre os sexos e estações do ano. Machos e fêmeas não apresentaram diferenças significativas, mas a prevalência de parasitismo foi mais elevada na estação quenteúmida que na estação fria-seca. Este padrão está de acordo com as observações de outros estudos com moscas da família Oestridae realizados nas áreas ao sul da região Neotropical, sugerindo a ocorrência de mudanças latitudinais nos picos de atividades reprodutivas destas moscas em relação às estações do ano ao longo destes sistemas. Este também é o primeiro registro da ocorrência de C. simulans em áreas mais ao sul da região Neotropical e do parasitismo de suas larvas em G. microtarsus.
Dieta de Micoureus demerarae (Thomas (Mammalia, Didelphidae associada às florestas contíguas de mangue e terra firme em Bragança, Pará, Brasil Diet of Micoreus demerarae (Thomas (Mammalia, Didelphidae associated with contiguous forests of mangrove and terra firme in Bragança, Pará, Brazil
Marcus E. B. Fernandes
Full Text Available A dieta de Micoureus demerarae (Thomas, 1905 foi estudada em bosques de mangue e terra firme através de amostras estomacais e fecais. O número de indivíduos capturados foi inversamente proporcional à disponibilidade de frutos e insetos, sendo Coleoptera e Hemiptera as ordens de artrópodes mais consumidos e Passifloraceae e Arecaceae os frutos mais ingeridos. Desse modo, tanto a maior variabilidade de frutos como a alta produção destes durante a estação seca, parecem explicar o aumento da captura desses animais nos bosques de terra firme, dos quais são originalmente provenientes. Os itens alimentares sugerem que esta espécie possui uma dieta do tipo onívora, independentemente da sazonalidade ou distribuição dos recursos disponíveis.The diet of Micoureus demerarae (Thomas, 1905 was studied in mangrove and terra firme stands by using stomachal and faecal samples. The number of captured individuals was inversely proportional to availability of fruits and insects, being Coleoptera and Hemiptera the most consumed arthropod orders and Passifloraceae and Arecaceae the most ingested fruits. Thus, either fruits variability or their high yield during the dry season seem to explain the increase of captured animals in the terra firme stands, where they originally come from. The food items suggest that this species has an omnivorous diet, independently of the seasonality or distribution of available resources.
Anomalous colour in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia and Arctocephalus australis (Otariidae, Carnivora Coloração anômala em mamíferos Neotropicais: uma revisão com novos registros para Didelphis sp. (Didelphidae, Didelphimorphia e Arctocephalus australis (Otariidae, Carnivora
Full Text Available Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp. in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.Colorações anômalas ocorrem em muitos vertebrados tropicais. Entretanto, estas são consideradas raras em populações selvagens, havendo poucos registros para a maioria dos táxons. Reportam-se, neste estudo, dois novos casos de coloração anômala em mamíferos. Além disso, por meio de uma extensa revisão bibliográfica, foram compilados os casos publicados sobre coloração anômala em mamíferos neotropicais entre 1950 e 2010. Cada registro foi classificado como albinismo, leucismo, piebaldismo ou, eventualmente, como coloração indeterminada. Como resultados, reportou-se o registro de um espécime leucístico de gambá (Didelphis sp. no sul do Brasil e de um espécime de lobo-marinho sul-americano (Arctocephalus australis com piebaldismo no norte do Uruguai. Também foram analisados 31 artigos científicos, resultando em 23 registros de albinismo, 12 de leucismo, 71 de piebaldismo e 92 registros classificados como de pigmentação indeterminada. A coloração anômala aparentemente é rara em pequenos mamíferos terrestres, mas é muito mais comum em cetáceos e microquirópteros. Dos 198 registros encontrados, 149 ocorreram em cetáceos e 30 em morcegos. No caso dos cetáceos, este resultado sugere que machos e fêmeas com este padrão anômalo de pigmentação são reprodutivamente exitosos e, consequentemente, sua frequência está aumentando nas populações naturais. Com relação aos morcegos, este fenômeno pode estar relacionado ao fato de estes animais orientarem-se primariamente por meio de ecolocalização e seus refúgios oferecerem proteção contra luz e predação. É possível que a coloração anômala ocorra mais frequentemente em outras ordens de mamíferos neotropicais, as quais não foram formalmente reportadas. Desta forma, mostra-se importante encorajar os pesquisadores a publicar estes eventos em vida selvagem para um melhor entendimento deste fenômeno, que tem influência significativa na sobrevivência destes organismos.
Aplin, K. P.; Rhind, S. G.; Ten Have, J.; Chesser, R. Terry
The Australian Brush-tailed Phascogale (Phascogale tapoatafa sensu lato) has a broad but highly fragmented distribution around the periphery of the Australian continent and all populations are under significant ongoing threat to survival. A new appraisal of morphological and molecular diversity within the group reveals that the population in the ‘Top End’ of the Northern Territory is specifically distinct from all others, including those in the Kimberley region of Western Australia to the west and on Cape York of Queensland to the east. The name P. pirata Thomas, 1904 is available for the ‘Top End’ taxon. Three geographically disjunct populations are distinguished at subspecies level within P. tapoatafa on a suite of external and cranio-dental features; these are found in southeast Australia from South Australia to mid-coastal Queensland (nominotypical tapoatafa), southwest Western Australia (wambenger subsp. nov.), and the Kimberley region of Western Australia (kimberleyensis subsp. nov.). A potential fourth subspecies occurs on Cape York but remains too poorly represented in collections for adequate characterization. Molecular divergence estimates based on partial sequences of the mitochondrial cytochrome b gene indicate that the range disjunction across southern Australia probably dates from the Late Pliocene, with the multiple disjunctions across northern Australia being more recent though almost certainly exceeding 400,000 years. An argument is made for the continued use of the subspecies rank in Australian mammalogy, despite a general lack of consistency in its current application.
Vullo , Romain; Gheerbrant , E.; Muizon , Chri; Neraudeau , Didier
International audience; We report the discovery of mammalian tribosphenic teeth from the basal Cenomanian of southwestern France that we refer to a new primitive marsupial-like form identified as a basal taxon of Mar- supialiformes, a new clade recognized here to include the crown group Marsupialia and primitive stem lineages more closely related to Marsupialia than to Deltatheroida. Arcantiodelphys marchandi gen et sp nov. shares several significant marsupial-like features (s.l.) with marsup...
Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae isolated from Didelphis aurita (Mammalia: Didelphidae in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade
Camila Madeira Tavares Lopes
Full Text Available BACKGROUND Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. OBJECTIVES We characterise a new species (Trypanosoma janseni n. sp. isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. METHODS The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp of the small subunit (18S ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. FINDINGS In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. CONCLUSIONS This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently know about the T. cruzi clade.
Trypanosoma janseni n. sp. (Trypanosomatida: Trypanosomatidae) isolated from Didelphis aurita (Mammalia: Didelphidae) in the Atlantic Rainforest of Rio de Janeiro, Brazil: integrative taxonomy and phylogeography within the Trypanosoma cruzi clade.
Lopes, Camila Madeira Tavares; Menna-Barreto, Rubem Figueiredo Sadok; Pavan, Márcio Galvão; Pereira, Mirian Cláudia De Souza; Roque, André Luiz R
Didelphis spp. are a South American marsupial species that are among the most ancient hosts for the Trypanosoma spp. We characterise a new species (Trypanosoma janseni n. sp.) isolated from the spleen and liver tissues of Didelphis aurita in the Atlantic Rainforest of Rio de Janeiro, Brazil. The parasites were isolated and a growth curve was performed in NNN and Schneider's media containing 10% foetal bovine serum. Parasite morphology was evaluated via light microscopy on Giemsa-stained culture smears, as well as scanning and transmission electron microscopy. Molecular taxonomy was based on a partial region (737-bp) of the small subunit (18S) ribosomal RNA gene and 708 bp of the nuclear marker, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes. Maximum likelihood and Bayesian inference methods were used to perform a species coalescent analysis and to generate individual and concatenated gene trees. Divergence times among species that belong to the T. cruzi clade were also inferred. In vitro growth curves demonstrated a very short log phase, achieving a maximum growth rate at day 3 followed by a sharp decline. Only epimastigote forms were observed under light and scanning microscopy. Transmission electron microscopy analysis showed structures typical to Trypanosoma spp., except one structure that presented as single-membraned, usually grouped in stacks of three or four. Phylogeography analyses confirmed the distinct species status of T. janseni n. sp. within the T. cruzi clade. Trypanosoma janseni n. sp. clusters with T. wauwau in a well-supported clade, which is exclusive and monophyletic. The separation of the South American T. wauwau + T. janseni coincides with the separation of the Southern Super Continent. This clade is a sister group of the trypanosomes found in Australian marsupials and its discovery sheds light on the initial diversification process based on what we currently know about the T. cruzi clade.
Sleeping sites of woolly mouse opossum Micoureus demerarae (Thomas (Didelphimorphia, Didelphidae in the Atlantic Forest of south-eastern Brazil Sítios de dormida da cuíca Micoureus demerarae (Thomas (Didelphimorphia, Didelphidaa na Floresta Atlântica do sudeste do Brasil
Edsel A. Moraes Junior
Full Text Available Micoureus demerarae (Thomas, 1905 is a medium-sized marsupial, around 130 g, with a nocturnal habit and insectivorous-omnivorous diet. From August 2001 to July 2002, seven individuals, three males and four females, were monitored with radio-telemetry in Reserva Biológica União, state of Rio de Janeiro, Brazil, aiming to investigate and describe the sleeping sites used by this marsupial. Fifty eight sleeping sites were located, most of which (70,7% in palm trees Astrocaryum aculeatissimum (Schott Burret, and the remaining in other tree species (29,3%, a significant difference (chi2 test; p Micoureus demerarae (Thomas, 1905 é um marsupial de tamanho médio, cerca de 130 g, de hábito noturno e arborícola e dieta insetívora-onívora. No período de agosto de 2001 a julho de 2002, sete indivíduos, três machos e quatro fêmeas, foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, com o objetivo de investigar e descrever os abrigos utilizados por essa espécie de marsupial. Foram localizados 58 abrigos, a maioria dos quais (70,7% em palmeiras Iri Astrocaryum aculeatissimum (Schott Burret e o restante em outras espécies de árvores (29,3%, uma diferença significativa (teste chi2; p < 0,005. Esta preferência por palmeiras não foi significativamente diferente entre os sexos (teste chi2; p = 0,920. Em 31 abrigos (53,4% do total o local exato onde o animal se encontrava pode ser localizado: nas palmeiras os animais sempre estavam alojados no local de inserção dos pecíolos junto ao tronco e a uma altura média de 4,66 ± 1,36 m, enquanto nas demais espécies de árvores, sete animais estavam em emaranhados de cipós e dois em ocos, a uma altura média de 10,67 ± 2,75 m. Esta diferença de altura entre abrigos em iris e não iris foi significativa (teste Mann Whitney; p < 0,001. Os resultados indicam que as palmeiras iris são um importante recurso para M. demerarae. A preferência por A. aculeatissimum se deve provavelmente à maior proteção contra predadores exercida pelos numerosos espinhos presentes nesta espécie.
route before reaching Lake Erie; and their flood plains contain the bulk of sefo prune areas in the Pennsylvania Coastal Communities. The U.S...leading variety, while sour cherries rank second. Other fruit crops of importance include cherries, peaches, apples, plums, prunes , and pears. Although...Lakefront Site (Spring, Summer and Fall) Species Common Name Spring Summer Fall Order Marsupialia Didelphis virginiana Virginia opossum X X X Order
Beck, Robin M D
The skull of the polydolopimorphian marsupialiform Epidolops ameghinoi is described in detail for the first time, based on a single well-preserved cranium and associated left and right dentaries plus additional craniodental fragments, all from the early Eocene (53-50 million year old) Itaboraí fauna in southeastern Brazil. Notable craniodental features of E. ameghinoi include absence of a masseteric process, very small maxillopalatine fenestrae, a prominent pterygoid fossa enclosed laterally by a prominent ectopterygoid crest, an absent or tiny transverse canal foramen, a simple, planar glenoid fossa, and a postglenoid foramen that is immediately posterior to the postglenoid process. Most strikingly, the floor of the hypotympanic sinus was apparently unossified, a feature found in several stem marsupials but absent in all known crown marsupials. "Type II" marsupialiform petrosals previously described from Itaboraí plausibly belong to E. ameghinoi ; in published phylogenetic analyses, these petrosals fell outside (crown-clade) Marsupialia. "IMG VII" tarsals previously referred to E. ameghinoi do not share obvious synapomorphies with any crown marsupial clade, nor do they resemble those of the only other putative polydolopimorphians represented by tarsal remains, namely the argyrolagids. Most studies have placed Polydolopimorphia within Marsupialia, related to either Paucituberculata, or to Microbiotheria and Diprotodontia. However, diprotodonty almost certainly evolved independently in polydolopimorphians, paucituberculatans and diprotodontians, and Epidolops does not share obvious synapomorphies with any marsupial order. Epidolops is dentally specialized, but several morphological features appear to be more plesiomorphic than any crown marsupial. It seems likely Epidolops that falls outside Marsupialia, as do morphologically similar forms such as Bonapartherium and polydolopids. Argyrolagids differ markedly in their known morphology from Epidolops but share some
Angelo Martins Fraga
Full Text Available Evolutionary adaptations in the morphology and physiology of cactus species have been associated to their mechanisms of dispersal and colonization. The dispersal mechanisms and modes of Opuntia monacantha (Willd. Haw. (Cactaceae were characterized in two beaches in Florianopolis, SC, Brazil. A marsupial from the genus Didelphis (Mammalia: Didelphidae was the only frugivorous and, thus, disperser of fruits, presenting specific eating places. The maritime hydrochory was due to the overwash on restinga vegetation, it is characterized by the dispersal of cladodes and fruits at various times of the year. It is here firstly described the sea action as a potential disperser for a cactus species.
Predação oportunista de Artibeus planirostris (Spix, 1823 e Carollia perspicillata (Linnaeus, 1758 (Chiroptera, Phyllostomidae por marsupiais e anuro na APA do Rio Curiaú, Amapá, Brasil Opportunistic predation of Artibeus planirostris (Spix, 1823 and Carollia perspicillata (Linnaeus, 1758 (Chiroptera, Phyllostomidae by marsupials and anuran in the APA do Rio Curiaú, Amapá State, Brazil
Isai Jorge de Castro
Full Text Available Durante estudos com morcegos em floresta de várzea na APA do Rio Curiaú, Amapá, Brasil, observamos três casos de predações oportunistas de morcegos frugívoros capturados em redes de neblina. Duas destas predações ocorreram por marsupiais e uma por anuro. Artibeus planirostris (Spix, 1823 (Chiroptera, Phyllostomidae foi predado por Didelphis marsupialis Linnaeus, 1758 e Philander opossum (Linnaeus, 1758 (Didelphimorphia, Didelphidae. Carollia perspicillata (Linnaeus, 1758 (Chiroptera, Phyllostomidae foi predado por Leptodactylus pentadactylus (Laurenti, 1768 (Anura, Leptodactylidae. A vocalização dos morcegos provavelmente atraiu os marsupiais para a rede, onde estes os predaram aproveitando que estavam presos. Este tipo de interação pode ocorrer naturalmente, no entanto, com maior dificuldade de registro.We observed three occasional predations of bats captured in mist nets by marsupials and a frog during studies in a várzea forest in the Amapá state. Artibeus planirostris (Spix, 1823 (Chiroptera, Phyllostomidae was preyed upon by Didelphis marsupialis Linnaeus, 1758 and Philander opossum (Linnaeus, 1758 (Didelphimorphia, Didelphidae. Carollia perspicillata (Linnaeus, 1758 (Chiroptera, Phyllostomidae was preyed on by Leptodactylus pentadactylus (Laurenti, 1768 (Anura, Leptodactylidae. The bats vocalizations probably attracted the marsupials and a frog to the mist nets where they preyed. This interaction form can occur naturally, however, are more difficult to observed.
Díaz-Delgado, J; Coimbra, A A C; Dos Santos-Cirqueira, C; Sanches, T C; Guerra, J M; de Oliveira, A S; Di Loretto, C; Zwarg, T; Ressio, R; Rivas, L; Sansone, M; Nagamori, F O; Kanamura, C; Gonçalves, P S; Fernandes, N C C A; Groch, K R; Catão-Dias, J L
The opossum (family Didelphidae) is a marsupial endemic to the Americas. Apart from the South American short-tailed opossum (Monodelphis domestica) and the Virginia opossum (Didelphis virginiana), there is considerable lack of knowledge about the health and diseases of most opossum species. Among these, the big-eared opossum (Didelphis aurita) is found in Argentina, Brazil and Paraguay. Natural and experimental studies have shown this species to be susceptible to infectious agents with zoonotic potential and the animals may play a role in transmission of such agents. However, neoplasia appears to be uncommon in this species. We describe the gross, microscopical and immunohistochemical features of a parotid salivary gland basal cell adenocarcinoma in a free-living big-eared opossum. This case represents the first report of salivary gland neoplasia in opossums. Copyright © 2017 Elsevier Ltd. All rights reserved.
Vullo, Romain; Gheerbrant, Emmanuel; de Muizon, Christian; Néraudeau, Didier
We report the discovery of mammalian tribosphenic teeth from the basal Cenomanian of southwestern France that we refer to a new primitive marsupial-like form identified as a basal taxon of Marsupialiformes, a new clade recognized here to include the crown group Marsupialia and primitive stem lineages more closely related to Marsupialia than to Deltatheroida. Arcantiodelphys marchandi gen et sp nov. shares several significant marsupial-like features (s.l.) with marsupialiform taxa known from the North American Mid-Cretaceous. Among marsupialiforms, it shows a closer resemblance to Dakotadens. This resemblance, which is plesiomorphic within "tribotherians," makes Arcantiodelphys one of the most archaic known Marsupialiformes. Moreover, Arcantiodelphys is characterized by an original and precocious crushing specialization. Both the plesiomorphic and autapomorphic characteristics of Arcantiodelphys among Marsupialiformes might be explained by an Eastern origin from Asian stem metatherians, with some in situ European evolution. In addition, the presence of a mammal with North American affinities in western Europe during the early Late Cretaceous provides further evidence of a large Euramerican biogeographical province at this age or slightly before. Concerning the paleobiogeographical history of the first stem marsupialiforms during the Albian-Cenomanian interval, 2 possible dispersal routes from an Asian metatherian ancestry can be proposed: Asia to Europe via North America and Asia to North America via Europe. The main significance of the Archingeay-Les Nouillers mammal discovery is that it indicates that the beginning of the stem marsupialiforms history involved not only North America but also Europe, and that this early history in Europe remains virtually unknown.
de Sousa, Keyla Carstens Marques; Fernandes, Marina Pugnaghi; Herrera, Heitor Miraglia; Benevenute, Jyan Lucas; Santos, Filipe Martins; Rocha, Fabiana Lopes; Barreto, Wanessa Teixeira Gomes; Macedo, Gabriel Carvalho; Campos, João Bosco; Martins, Thiago Fernandes; de Andrade Pinto, Pedro Cordeiro Estrela; Battesti, Darci Barros; Piranda, Eliane Mattos; Cançado, Paulo Henrique Duarte; Machado, Rosangela Zacarias; André, Marcos Rogério
Hepatozoon parasites comprise intracellular apicomplexan parasites transmitted to vertebrate animals by ingestion of arthropods definitive hosts. The present work aimed to investigate the occurrence of Hepatozoon spp. in wild animals, domestic dogs and their respective ectoparasites, in southern Pantanal region, central-western Brazil, by molecular techniques. Between August 2013 and March 2015, 31 coatis (Nasua nasua), 78 crab-eating foxes (Cerdocyon thous), seven ocelots (Leopardus pardalis), 42 dogs (Canis lupus familiaris), 110 wild rodents (77 Thichomys fosteri, 25 Oecomys mamorae, and 8 Clyomys laticeps), 30 marsupials (14 Thylamys macrurus, 11 Gracilinanus agilis, 4 Monodelphis domestica and 1 Didelphis albiventris), and 1582 ticks and 80 fleas collected from the sampled animals were investigated. DNA samples were submitted to PCR assays for Hepatozoon spp. targeting 18S rRNA gene. Purified amplicons were directly sequenced and submitted to phylogenetic analysis. A high prevalence of Hepatozoon among carnivores (C. thous [91.02%], dogs [45.23%], N. nasua [41.9%] and L. pardalis [71.4%]) was found. However, ticks and fleas were negative to Hepatozoon PCR assays. By phylogenetic analysis based on 18S rRNA sequences, Hepatozoon sequences amplified from crab-eating foxes, dogs, coatis and ocelots clustered with sequences of H. canis, H. americanum and H. felis. The closely related positioning of Hepatozoon sequences amplified from wild rodents and T. macrurus marsupial to Hepatozoon from reptiles and amphibians suggest a possible transmission of those Hepatozoon species between hosts by ectoparasites or by predation. Hepatozoon haplotypes found circulating in wild rodents seem to present a higher degree of polymorphism when compared to those found in other groups of animals. Although rodents seem not to participate as source of Hepatozoon infection to wild carnivores and domestic dogs, they may play an important role in the transmission of Hepatozoon to reptiles
Orozco, M M; Enriquez, G F; Cardinal, M V; Piccinali, R V; Gürtler, R E
Understanding the complex epidemiology of Trypanosoma cruzi transmission cycles requires comparative studies in widely different environments. We assessed the occurrence of T. cruzi infection in sylvatic mammals, their infectiousness to the vector, and parasite genotypes in a protected area of the Argentine Chaco, and compared them with information obtained similarly in a nearby disturbed area. A total of 278 mammals from >23 species in the protected area were diagnosed for T. cruzi infection using xenodiagnosis, kDNA-PCR and nuclear satellite DNA-PCR (SAT) from blood samples. The relative abundance and species composition differed substantially between areas. Didelphis albiventris opossums were less abundant in the protected area; had a significantly lower body mass index, and a stage structure biased toward earlier stages. The capture of armadillos was lower in the protected area. The composite prevalence of T. cruzi infection across host species was significantly lower in the protected area (11.1%) than in the disturbed area (22.1%), and heterogeneous across species groups. The prevalence of infection in D. albiventris and Thylamys pusilla opossums was significantly lower in the protected area (nil for D. albiventris), whereas infection in sigmodontine rodents was three times higher in the protected area (17.5 versus 5.7%). Parasite isolates from the two xenodiagnosis-positive mammals (1 Dasypus novemcinctus and 1 Conepatus chinga) were typed as TcIII; both specimens were highly infectious to Triatoma infestans. Fat-tailed opossums, bats and rodents were kDNA-PCR-positive and xenodiagnosis-negative. Desmodus rotundus and Myotis bats were found infected with T. cruzi for the first time in the Gran Chaco. Copyright © 2015 Elsevier B.V. All rights reserved.
Elsheikha, Hany M; Fitzgerald, Scott D; Mansfield, Linda S; Saeed, A Mahdi
This report describes the newly identified Sarcocystis inghami n. sp. from the skeletal muscles of opossums (Mammalia: Didelphidae) that were collected from south central Michigan (42 degrees 43'-42 degrees 79'N, 84 degrees 18'-84 degrees 86'W), USA. The new species is distinguished from all species described from North and South American opossums by the distinctive morphology of the villar protrusions on the cyst wall. Sarcocysts of S. inghami are microscopic, up to 700 microm long and 110 microm wide. The sarcocyst wall is up to 7 microm thick, with long, stalked protrusions which average 5.5 x 1.2 microm. These are constricted at the base, expanded laterally, rounded off distally and occasionally bifid. The villar protrusions have numerous microtubules without electron-dense bodies that extend from the tips into the granular layer. Bradyzoites are 10.7 x 4.3 (8-12 x 4-5) microm. This is the second species of Sarcocystis sarcocyst described from the Virginia opossum in North America.
Woods, Henri A; Hellgren, Eric C
Semelparity, which is multiplying once in a lifetime, is a rare reproductive strategy among mammals. Several species of the marsupial family Dasyuridae experience 100% male mortality following an intense mating period. We investigated seasonal physiological changes that may be associated with early mortality in the male Virginia opossum (Didelphis virginiana; Didelphidae) and compared these changes with those of semelparous, male dasyurids. Free-ranging male Virginia opossums (n=36) were collected during 2001 at the Oklahoma State University Cross Timbers Experimental Range. Seasonal data were collected on hematological, morphological, and helminth parameters of these individuals. We used one-way ANOVA to determine whether there were seasonal differences among means for each parameter. It appeared that male Virginia opossums experienced some physiological changes similar to those of male dasyurids exhibiting semelparity. All males collected in summer (August) were juveniles of the year. Lack of adult males in August suggests high mortality of this cohort during the breeding season. Opossum characteristics exhibiting the dasyurid semelparity syndrome included packed cell volume, adrenal mass, and helminth numbers. Minor lymphocytopenia, neutrophilia, and testosterone concentrations also were similar to semelparous dasyurids. However, a lack of change in serum cortisol concentration and body mass and dynamics in immunoglobulin protein, serum protein, and testes mass were not consistent with previous reports of semelparous dasyurid physiology. Evolutionary divergence and differences in breeding behavior between dasyurids and didelphids may be responsible for the lack of consistency between the taxa.
Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n1p47 Adaptações evolutivas na morfologia e fisiologia das cactáceas têm sido associadas aos seus mecanismos de dispersão e colonização. Os mecanismos e modos de dispersão de Opuntia monacantha (Willd. Haw. (Cactaceae foram caracterizados em duas praias de Florianópolis, SC, Brasil. Um marsupial do gênero Didelphis (Mammalia: Didelphidae foi o único frugívoro e, portanto, dispersor de frutos, apresentando locais específicos para alimentação. A hidrocoria marítima ocorreu após a invasão marinha sobre a vegetação de restinga, caracterizando-se pela dispersão de cladódios e frutos em várias épocas do ano. Descreve-se pela primeira vez a ação do mar como potencial dispersor para uma espécie de cactos.
Walfrido Moraes Tomas
Full Text Available Abstract We updated the checklist of mammals from Mato Grosso do Sul, Brazil based on primary records only. One hundred and sixty-six mammal species were listed as occurring in the state, 47 of them being medium to large, 47 small mammal and 73 bat species. The listed species are distributed in 31 families: Didelphidae (17 spp., Dasypodidae (7 spp., Myrmecophagidae (2 spp., Cebidae (1 sp., Callithrichidae (2 spp., Aotidae (1 sp., Pitheciidae (1 sp., Atelidae (1 sp., Leporidae (1 sp., Felidae (7 spp., Canidae (4 spp., Mustelidae (5 spp., Mephitidae (2 spp., Procyonidae (2 spp., Tapiridae (1 sp., Tayassuidae (2 spp., Cervidae (4 spp., Sciuridae (1 sp., Cricetidae (22 spp., Erethizontidae (1 sp., Caviidae (3 spp., Dasyproctidae (1 sp., Cuniculidae (1 sp., Echimyidae (4 spp., Phyllostomidae (41 spp., Emballonuridae (2 spp., Molossidae (16 spp., Vespertilionidae (9 spp., Mormoopidae (1 sp., Noctilionidae (2 spp., and Natalidade (1 sp.. These numbers represent an increase of fourteen species with primary records for the state in comparison with the previously published checklist. However, it is evident the scarcity of information at several regions of the state, and the need of implementation of regional zoological collections. The state of Mato Grosso do Sul represent only 4.19% of the Brazilian territory, but the number of mammal species reach 24.13% of the known species occurring in the country.
Munemasa, Maruo; Nikaido, Masato; Nishihara, Hidenori; Donnellan, Stephen; Austin, Christopher C; Okada, Norihiro
Although recent mammalian genome projects have uncovered a large part of genomic component of various groups, several repetitive sequences still remain to be characterized and classified for particular groups. The short interspersed repetitive elements (SINEs) distributed among marsupial genomes are one example. We have identified and characterized two new SINEs from marsupial genomes that belong to the CORE-SINE family, characterized by a highly conserved "CORE" domain. PCR and genomic dot blot analyses revealed that the distribution of each SINE shows distinct patterns among the marsupial genomes, implying different timing of their retroposition during the evolution of marsupials. The members of Mar3 (Marsupialia 3) SINE are distributed throughout the genomes of all marsupials, whereas the Mac1 (Macropodoidea 1) SINE is distributed specifically in the genomes of kangaroos. Sequence alignment of the Mar3 SINEs revealed that they can be further divided into four subgroups, each of which has diagnostic nucleotides. The insertion patterns of each SINE at particular genomic loci, together with the distribution patterns of each SINE, suggest that the Mar3 SINEs have intensively amplified after the radiation of diprotodontians, whereas the Mac1 SINE has amplified only slightly after the divergence of hypsiprimnodons from other macropods. By compiling the information of CORE-SINEs characterized to date, we propose a comprehensive picture of how SINE evolution occurred in the genomes of marsupials.
Full Text Available This paper presents an analysis of vertebrate roadkills in five different habitats of tropical South America. Observations of vertebrate roadkills were conducted in 1978, on a 572 km road between Caracas and Mantecal/Apure in Venezuela, during the rainy season (June-October. During five passages on this route, which includes five distinct habitats, 79 vertebrate carcasses - mammals and reptiles - were found. If we assume that the carcasses remain for two days on the road, vehicles can be expected to strike 350 spectacled caimans Caiman crocodilus Linnaeus, 1758 (Alligatoridae during the rainy season alone. Similar calculations for other species yield 313 snakes and lizards, 294 opossums Didelphis marsupialis Linnaeus, 1758 (Didelphidae, 220 crab-eating foxes Cerdocyon thous (Linnaeus, 1776 (Canidae, 129 tamanduas Tamandua tetradactyla (Linnaeus, 1758 (Myrmecophagidae, 55 capybaras Hydrochaerus hydrochaeris (Linnaeus, 1766 (Hydrochaeridae and 37 eastern cottontails Sylvilagus floridanus Allen, 1890 (Leporidae. Numerous papers have been published on vertebrates killed by vehicles on roads in Europe, North America, and Australia, and several papers are available regarding vertebrate roadkills in Africa and Asia. From South America there are several papers on vertebrates, birds, and mammals, whereas from Venezuela only one and it deals with iguanas (Iguana iguana Linnaeus, 1758, Iguanidae.Este trabalho apresenta uma análise de vertebrados mortos em estrada em cinco habitats tropicais diferentes na América do Sul. As observações dos vertebrados mortos em estrada foram feitas em 1978, a 572 km da rodovia entre Caracas e Mantecal/Apure na Venezuela, durante a estação das chuvas (junho-outubro. Durante cinco passagens nesta rota, a qual inclui cinco habitats diferentes, foram encontradas 79 carcaças de vertebrados - répteis e mamíferos. Assumindo que as carcaças permaneçam por dois dias na estrada, é esperado que veículos matem 350
María Mónica Díaz
Full Text Available In this work the infestation with I. luciae on Didelphimorphia and Rodentia in different environments of Peruvian Amazon was studied. Didelphimorphia was represented by the family Didelphidae. Specimens belonging to Caluromys lanatus, Didelphis marsupialis, Marmosops sp.2, Metachirus nudicaudatus, Philander andersoni and Philander opossum were infested with adults I. luciae and one Micoureus sp. was infested with larvae. In Rodentia, the infestation with I. luciae nymphs was restricted to Hylaeamys perenensis, Hylaeamys yunganus and Oligoryzomys microtis, while one Oecomys bicolor (all Cricetidae was infested with larvae of this species. The few larvae were found on rodents captured in primary forest. The only significant difference (P No presente trabalho, infestações por Ixodes luciae em Didelphimorphia e Rodentia em diferentes ambientes da Amazônia peruana foram estudadas. Didelphimorphia foi representada pela família Didelphidae. Espécimes pertencentes a Caluromys lanatus, Didelphis marsupialis, Marmosops sp., Metachirus nudicaudatus, Philander andersoni e Philander opossum foram encontrados infestadas por adultos de I. luciae; um Micoureus sp. foi encontrado infestado por larvas. Em Rodentia, a infestação por ninfas de I. luciae estiveram restritas a Hylaeamys perenensis, Hylaeamys yunganus e Oligoryzomys microtis, enquanto que um Oecomys bicolor (todos Cricetidae esteve infestado por larvas de I. luciae. As poucas larvas foram encontradas em roedores capturados na floresta primária. A única diferença significante (P < 0.05 na prevalência de carrapatos adultos em Didelphimorphia foi entre P. andersoni e M. nudicaudatus (distribuição chi-quadrado. A distribuição de carrapatos adultos foi significativamente diferente em P. andersoni quando comparado com M. nudicaudatus, P. opossum e D. marsupialis (teste Kruskal-Wallis. Nenhum efeito significante do mês ou ambiente foi observado em relação à infestação por carrapato
Kaliane A.R. Paiva
Full Text Available RESUMO: O presente estudo teve como objetivo registrar a ocorrência de Rickettsia sp. em roedores e marsupiais nativos da Estação Experimental Rafael Fernandes da UFERSA, Mossoró/RN. O trabalho consistiu em uma pesquisa de campo, com roedores e marsupiais silvestres, com os dados expressos em frequência simples e porcentagem através do programa estatístico IBM SPSS (Armonk, NY: IBM Corp., versão 22.0. Coletaram-se amostras de plasma sanguíneo de marsupiais (36 e de roedores (5. Destes, 64 continham Amblyomma auricularium, 7 Amblyomma parvum e 12 Amblyomma sp. As amostras de plasma sanguíneo foram analisadas através da técnica de Reação de Imunofluorescência Indireta. Exemplares de A. auricularium e a A. parvum foram macerados e submetidos a Técnica de Reação em Cadeia da Polimerase. Das amostras de plasma testadas, 17,60% apresentaram soropositividade para Rickettsia amblyommii. Oito exemplares de A. auricularium estavam positivos para R. amblyommii na análise de fragmentos dos genes gltA (350 bp e ompA (587 pb, com 100% de similaridade com Candidatus R. amblyommii estirpe Bahia e AaPE, correspondendo a uma baixa circulação do agente dentre os vetores e hospedeiros. Esta pesquisa registra pela primeira vez a ocorrência de R. amblyommii em marsupiais Gracilinanus agilis e Monodelphis domestica pertencentes a Família Didelphidae, e roedores das Famílias Echimyidae e Cricetidae, cujas espécies foram Thrichomys sp. e Wiedomys sp., respectivamente, em Mossoró, estado do Rio Grande do Norte.
Voss, Robert S; Jansa, Sharon A
Mammals that prey on venomous snakes include several opossums (Didelphidae), at least two hedgehogs (Erinaceidae), several mongooses (Herpestidae), several mustelids, and some skunks (Mephitidae). As a group, these taxa do not share any distinctive morphological traits. Instead, mammalian adaptations for ophiophagy seem to consist only in the ability to resist the toxic effects of snake venom. Molecular mechanisms of venom resistance (as indicated by biochemical research on opossums, mongooses, and hedgehogs) include toxin-neutralizing serum factors and adaptive changes in venom-targeted molecules. Of these, toxin-neutralizing serum factors have received the most research attention to date. All of the toxin-neutralizing serum proteins discovered so far in both opossums and mongooses are human α1B-glycoprotein homologs that inhibit either snake-venom metalloproteinases or phospholipase A(2) myotoxins. By contrast, adaptive changes in venom-targeted molecules have received far less attention. The best-documented examples include amino-acid substitutions in mongoose nicotinic acetylcholine receptor that inhibit binding by α-neurotoxins, and amino-acid substitutions in opossum von Willebrand factor (vWF) that are hypothesized to weaken the bond between vWF and coagulopathic C-type lectins. Although multiple mechanisms of venom resistance are known from some species, the proteomic complexity of most snake venoms suggests that the evolved biochemical defences of ophiophagous mammals are likely to be far more numerous than currently recognized. Whereas most previous research in this field has been motivated by the potential for medical applications, venom resistance in ophiophagous mammals is a complex adaptation that merits attention from comparative biologists. Unfortunately, evolutionary inference is currently limited by ignorance about many relevant facts that can only be provided by future research. © 2012 The Authors. Biological Reviews © 2012 Cambridge
Diogo, Rui; Bello-Hellegouarch, Gaelle; Kohlsdorf, Tiana; Esteve-Altava, Borja; Molnar, Julia L
Opossums are frequent subjects of developmental studies because marsupials share developmental features not seen in placentals and because Didelphimorpha is the sister-group of other extant Marsupialia. But is the adult marsupial muscular system markedly different from that of placentals or is it, like the skeletal system, very similar? We provide, for the first time, a brief description of all head and limb muscles of Didelphis virginiana based on our dissections and using a unifying nomenclature by integrating the data gathered in our long-term project on the development, homologies, and evolution of the muscles of all major vertebrate taxa. Our data indicate that there were many more muscle synapomorphic changes from the last common ancestor (LCA) of amniotes to the mammalian LCA (63) and from this LCA to the LCA of extant therians (48) than from this latter LCA to the LCA of extant placentals (10 or 11). Importantly, Didelphis is anatomically more plesiomorphic (only 14 changes from LCA of extant therians) than are rats (37 changes) and humans (63 changes), but its musculature is more complex (193 muscles) than that of humans (only 180 muscles). Of the 194 muscles of Didelphis, 172 (89%) are present in rats, meaning that their adult muscle anatomy is indeed very similar. This similarity supports the existence of a common, easy recognizable therian Bauplan, but one that is caused by developmental constraints and by evolutionary change driven by the needs of the embryos/neonates, rather than by a "goal" toward a specific adult plan/"archetype," as the name Bauplan suggests. Anat Rec, 299:1224-1255, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Daxner-Höck, Gudrun; Badamgarav, Demchig; Barsbold, Rinchen; Bayarmaa, Baatarjav; Erbajeva, Margarita; Göhlich, Ursula Bettina; Harzhauser, Mathias; Höck, Eva; Höck, Volker; Ichinnorov, Niiden; Khand, Yondon; López-Guerrero, Paloma; Maridet, Olivier; Neubauer, Thomas; Oliver, Adriana; Piller, Werner; Tsogtbaatar, Khishigjav; Ziegler, Reinhard
Cenozoic sediments of the Taatsiin Gol and TaatsiinTsagaan Nuur area are rich in fossils that provide unique evidence of mammal evolution in Mongolia. The strata are intercalated with basalt flows. 40 Ar/ 39 Ar data of the basalts frame the time of sediment deposition and mammal evolution and enable a composite age chronology for the studied area. We investigated 20 geological sections and 6 fossil localities of Oligocene and early Miocene deposits from this region. Seventy fossil beds yielded more than 19,000 mammal fossils. This huge collection encompasses 175 mammal species: 50% Rodentia, 13% Eulipotyphla and Didelphomorphia, and 12% Lagomorpha. The remaining 25% of species are distributed among herbivorous and carnivorous large mammals. The representation of lower vertebrates and gastropods is comparatively poor. Several hundred SEM images illustrate the diversity of Marsupialia, Eulipotyphla, and Rodentia dentition and give insight into small mammal evolution in Mongolia during the Oligocene and early Miocene. This dataset, the radiometric ages of basalt I (∼31.5 Ma) and basalt II (∼27 Ma), and the magnetostratigraphic data provide ages of mammal assemblages and time ranges of the Mongolian biozones: letter zone A ranges from ∼33 to ∼31.5 Ma, letter zone B from ∼31.5 to ∼28 Ma, letter zone C from ∼28 to 25.6 Ma, letter zone C1 from 25.6 to 24 Ma, letter zone C1-D from 24 to ∼23 Ma, and letter zone D from ∼23 to ∼21 Ma.
Coelho, Marcella Gonçalves; Ramos, Vanessa do Nascimento; Limongi, Jean Ezequiel; de Lemos, Elba Regina Sampaio; Guterres, Alexandro; da Costa Neto, Sócrates Fraga; Rozental, Tatiana; Bonvicino, Cibele Rodrigues; D'Andrea, Paulo Sérgio; Moraes-Filho, Jonas; Labruna, Marcelo Bahia; Szabó, Matias Pablo Juan
Sources of pathogenic Rickettsia in wildlife are largely unknown in Brazil. In this work, potential tick vectors and seroreactivity of small mammals against four spotted-fever group Rickettsia (R. rickettsii, R. parkeri, R. amblyommii and R. rhipicephali) and Rickettsia bellii from peri-urban areas of Uberlândia, a major town in Brazil, are described for the first time. Small mammals were captured and blood samples collected. Ticks were collected from the surface of the host and the environment and posteriorly identified. Reactivity of small mammal sera to Rickettsia was tested by indirect immunofluorescence assay (IFA) using crude antigens from five Brazilian Rickettsia isolates. Information was obtained from 416 small mammals (48 Marsupialia and 368 Rodentia). Forty-eight animals were parasitized and two tick species, Ixodes loricatus and Amblyomma dubitatum, were found on several host species, with a few tick-host relationships described for the first time. From the 416 tested sera, 70 reacted to at least one Rickettsia antigen (prevalence of 16.8%) and from these, 19 (27.1%) reacted to two or more antigens. Seroprevalence was higher for marsupials (39.6%) than for rodents (13.8%). Marsupial and Rhipidomys spp. sera reacted mainly (highest seroprevalence and titers) to R. bellii, and that of Necromys lasiurus mainly to R. rickettsii. Although the serologic assays poorly discriminate between closely related spotted-fever group Rickettsia, the observed small mammal seroreactivity suggests the circulation of Rickettsia in the peri-urban area of Uberlândia, albeit at low levels.
Full Text Available Abstract Background- Parent-specific methylation of specific CpG residues is critical to imprinting in eutherian mammals, but its importance to imprinting in marsupials and, thus, the evolutionary origins of the imprinting mechanism have been the subject of controversy. This has been particularly true for the imprinted Insulin-like Growth Factor II (IGF2, a key regulator of embryonic growth in vertebrates and a focal point of the selective forces leading to genomic imprinting. The presence of the essential imprinting effector, DNMT3L, in marsupial genomes and the demonstration of a differentially methylated region (DMR in the retrotransposon-derived imprinted gene, PEG10, in tammar wallaby argue for a role for methylation in imprinting, but several studies have found no evidence of parent-specific methylation at other imprinted loci in marsupials. Results- We performed the most extensive search to date for allele-specific patterns of CpG methylation within CpG isochores or CpG enriched segments across a 22 kilobase region surrounding the IGF2 gene in the South American opossum Monodelphis domestica. We identified a previously unknown 5'-untranslated exon for opossum IGF2, which is flanked by sequences defining a putative neonatal promoter, a DMR and an active Matrix Attachment Region (MAR. Demethylation of this DMR in opossum neonatal fibroblasts results in abherrant biallelic expression of IGF2. Conclusion- The demonstration of a DMR and an active MAR in the 5' flank of opossum IGF2 mirrors the regulatory features of the 5' flank of Igf2 in mice. However, demethylation induced activation of the maternal allele of IGF2 in opossum differs from the demethylation induced repression of the paternal Igf2 allele in mice. While it can now be concluded that parent-specific DNA methylation is an epigentic mark common to Marsupialia and Eutheria, the molecular mechanisms of transcriptional silencing at imprinted loci have clearly evolved along independent
Flavio da Fonseca
Full Text Available A new tick, Amblyomma parkeri, n. sp., is described as a parasite of Coendu sp. from S. Paulo, Brazil. Female holotype, nymph and larva are described (Figs. 2 e 3. The n. sp. differs completly from Koch's species Amblyomma longirostre, the common parasite of the Erethizotidae. Standard data for measures of the female dorsal scutum ixodidae are proposed as follows (fig. 1: PA = Antero-posterior; PB = Postero-basal; PM = Postero-median; TT = Transversal; OO = Inter-ocular; OT= Occulo-transversal; SS = Inter-scapular; CC = Cervical; PT = Postero-transversal; ST = Scapulo-transversal; NPT = Normal to the postero-transversal; NST = Normal to the scapulo-transversal. In the female holotype the standard data are as follows: PA = 2.00 mm; PB = 2.26 mm; PM = 1.10 mm; TT = 2.20 mm; OO = 2.26 mm; SS = 0,84 mm; CC = 0.63 mm; SC = 0.12 mm; NPT = 0.20mm; STN = 0.1 mm. Peritrema 0.80 x 0.42 mm with a narrow postero-internal angle and a large, elongated macula. Coxa I with two short spines and all other coxae with only one shorter spine, shortest in coxa IV. Hypostoma spatulated with formula 3/3. Gnathosoma 1.42 mm long and basis 0.63 mm long by 0.84 greatest wide. Palpi with smoth external surface, 1.00 mm long. Type lot No. 4458 from Cotia, S. Paulo, Brazil; in the acarological collection of the Escola Paulista de Medicina, S. Paulo. Ixodes didelphidis, n. sp., differing from Ixodes loricatus Neumann by the shape of the peritremata (figs. 4 a 5 of the male and female and by the number of the punctations in this organ is described form Didelphidae, Muridae and Cavidae. Twenty eight lots were obtained from Anápolis, Goiás, Brasil, where I. loricatus is subtituded by the n. sp. under description. Comparison with NEUMANN'S types of I. loricatus was possible through the courtesy of Prof. A. BRIZARD from Toulouse, who kindly loaned NEUMANN'S material. Female cotypes N° 40 and male allotype N° 531 in the Collection of Ixodidae of the Oswaldo Cruz Institute.
Gonçalves, Fernando; Hannibal, Wellington; Godoi, Mauricio N; Martins, Fernando I; Oliveira, Roniel F; Figueiredo, Valquiria V; Casella, Janaina; de Sá, Érica F G G
The data set represents the first attempt at a large-scale inventory of non-volant mammals, with potential applications to performing macroecological studies, developing conservation strategies, and undertaking population and community ecology research, but also to evaluate the ecological consequences of fragmentation and defaunation. Our objectives for compiling these data were to summarize information about inventories of non-volant mammals in the critically important area of the Upper Paraná River Basin by focusing on species richness and index of frequency of occurrence and to identify gaps in knowledge regarding non-volant mammal communities in order to guide future sampling efforts. The data set comprises studies on communities of non-volant mammals from 52 locations covering more than 1,000 km 2 and comprises portion of four Brazilian states in the Upper Paraná River Basin. We listed 81 species of non-volant mammals distributed among 58 genera, 22 families, and 9 orders. Rodentia (28 species) was the richest order, followed by Carnivora (17 spp.) and Didelphimorphia (15 spp.). The richest family was Cricetidae (20 spp.), followed by Didelphidae (15 spp.), and Dasypodidae and Felidae (six spp.). Considering national conservation status, one species are considered endangered and 16 vulnerable. Considering global conservation status, 7 species are considered vulnerable, 10 are considered near threatened, and 6 are data deficient. According to the index of frequency of occurrence, Myrmecophaga tridactyla was the most frequent species, occurring at 88.64% of all sites, while 25 species were considered very restricted, occurring in just 2.56% of all sites. In general, the non-volant mammal fauna was composed of mainly very restricted (VR, 25 species) and localized species (L, 25 species), which account for 61.7% of the known species, while 38.3% are restricted (R, 8 species), common (C, 16 species), and widespread (W, 7 species). Seven marsupials and five
Jose Rodrigues Coura
Full Text Available From an epidemiological point of view, Chagas disease and its reservoirs and vectors can present the following characteristics: (i enzooty, maintained by wild animals and vectors, with broad occurrence from southern United States of America (USA to southern Argentina and Chile (42ºN 49ºS, (ii anthropozoonosis, when man invades the wild ecotope and becomes infected with Trypanosoma cruzi from wild animals or vectors or when the vectors and wild animals, especially marsupials, invade the human domicile and infect man, (iii zoonosis-amphixenosis and exchanged infection between animals and humans by domestic vectors in endemic areas and (iv zooanthroponosis, infection that is transmitted from man to animals, by means of domestic vectors, which is the rarest situation in areas endemic for Chagas disease. The characteristics of Chagas disease as an enzooty of wild animals and as an anthropozoonosis are seen most frequently in the Brazilian Amazon and in the Pan-Amazon region as a whole, where there are 33 species of six genera of wild animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra, Carnivora and Primata and 27 species of triatomines, most of which infected with T. cruzi . These conditions place the resident populations of this area or its visitors - tourists, hunters, fishermen and especially the people whose livelihood involves plant extraction - at risk of being affected by Chagas disease. On the other hand, there has been an exponential increase in the acute cases of Chagas disease in that region through oral transmission of T. cruzi , causing outbreaks of the disease. In four seroepidemiological surveys that were carried out in areas of the microregion of the Negro River, state of Amazonas, in 1991, 1993, 1997 and 2010, we found large numbers of people who were serologically positive for T. cruzi infection. The majority of them and/or their relatives worked in piassava extraction and had come into contact with and were stung by
I. A. Sherlock
Full Text Available Durante os anos de 1982 a 1986, a investigação sobre mamíferos comensais e silvestres, da periferia da cidade de Jacobina, Bahia, mostrou, ao lado do escasso número de exemplares, uma reduzida variedade específica dessa fauna. Capturou-se apenas 11 espécies, entre as quais, predominou o Didelphis albiventris, que abrangeu 44% dos 213 espécimens capturados. Entre os 193 com exames já concluídos, 84 eram exemplares de D. albiventris e 2 estavam infectados pela Leishmania donovani senso lato, 1 por L. mexicana amazonensis, 1 por L. braziliensis, subespécie e 3 por Trypanosoma cruzi Também foram observadas formas suspeitas de serem amastigotas de leishmanics, nos esfregaços de órgãos de 3 exemplares de Dasyprocta aguti, 1 Cercomys cunicularius - e 1 Oryzomys eliurus. 0 restante dos exemplares, inclusive 14 de Lycalopex vetulus, estava negativo para flagelados. Apesar de reforçado por outros indicadores epidemiológicos, como a predominância específica, a freqüência domiciliar, a atratividade para a vetora Lutzomyia longipalpis, e a concomitância com casos humanos nos mesmos locais, o índice de 2,3% de infecção natural do Didelphis albiventris, não autoriza a conclusão definitiva de ser o marsupial o mais importante reservatório natural da leishmaniose visceral em Jacobina.From 1982 to 1986, investigations on the natural infection with leishmanias of the sylvatic and commensal mammals were carried out around the city of Jacobina, Bahia, one of the oldest endemic foci of visceral leishmaniasis in Brazil. The species of Marsupialia Didelphis albiventris predominated, with the rate of 44%, over the total of 213 specimens belonging to only 11 different species of mammals collected there. Among the 84 specimens of D. albiventris examined, 2(2.3% were infected with Leishmania donovani sensu lato; 1 with L. mexicana amazonensis, 1 with L. braziliensis sub species, and 3 with Trypanosoma cruzi. Also, amastigote suspected bodies were