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Sample records for rhyncholestes raphanurus paucituberculata

  1. Dental anomalies in Dromiciops gliroides (Microbiotheria, Microbiotheriidae), Caenolestes fuliginosus and Rhyncholestes raphanurus (Paucituberculata, Caenolestidae) Anomalías en la dentición de Dromiciops gliroides (Microbiotheria, Microbiotheriidae), Caenolestes fuliginosus and Rhyncholestes raphanurus (Paucituberculata, Caenolestidae)

    OpenAIRE

    Martin, Gabriel M.

    2007-01-01

    Dental anomalies are described after analyzing series of skulls and mandibles of three species of South American marsupials: the monito del monte {Dromiciops gliroides), the silky shrew-opossum {Caenolestes fuliginosus) and the Chilean shrew-opossum {Rhyncholestes raphanurus). The anomalies are classified into three categories: (1) supernumerary or missing teeth in normal positions of the dental series, (2) morphological anomalies like teeth fusion or anomalous crown shape, and (3) presence o...

  2. Dental anomalies in Dromiciops gliroides (Microbiotheria, Microbiotheriidae, Caenolestes fuliginosus and Rhyncholestes raphanurus (Paucituberculata, Caenolestidae Anomalías en la dentición de Dromiciops gliroides (Microbiotheria, Microbiotheriidae, Caenolestes fuliginosus and Rhyncholestes raphanurus (Paucituberculata, Caenolestidae

    Directory of Open Access Journals (Sweden)

    GABRIEL M MARTIN

    2007-12-01

    Full Text Available Dental anomalies are described after analyzing series of skulls and mandibles of three species of South American marsupials: the monito del monte {Dromiciops gliroides, the silky shrew-opossum {Caenolestes fuliginosus and the Chilean shrew-opossum {Rhyncholestes raphanurus. The anomalies are classified into three categories: (1 supernumerary or missing teeth in normal positions of the dental series, (2 morphological anomalies like teeth fusion or anomalous crown shape, and (3 presence of teeth in unusual positions. Cusp fusion and supernumerary teeth at the end of the toothrow have been observed predominantly in D. gliroides. A tendency to find supernumerary or missing teeth is observed between the procumbent incisors and the second lower premolars in caenolestids. Possible causes for these anomalies and their morphofunctional value are discussed. A comparison with other marsupials is presented and discussed. Isolation of local populations and its effects on genetic drift processes might explain the high percentage of dental anomaliesA partir del análisis de series de cráneos y mandíbulas del monito de monte {Dromiciops gliroides, el ratón marsupial sedoso {Caenolestes fuliginosus y la comadrejita trompuda {Rhyncholestes raphanurus, se describen las anomalías en la dentición (incisivos, premolares, molares, clasificándose de acuerdo a tres categorías: (1 dientes supernumerarios o faltantes en alguna posición, (2 anomalías morfológicas tales como fusión de dientes o variaciones en el número de raíces, y (3 presencia de dientes en posiciones inusuales. Se observa una tendencia al desarrollo de dientes supernumerarios en cenoléstidos, o pérdida de elementos dentarios en la mandíbula, principalmente entre los incisivos procumbentes y el segundo premolar. En D. gliroides, la tendencia es hacia la fusión de cúspides y la producción de dientes supernumerarios al final de la hilera molar superior (apareciendo como M5. Se discuten las

  3. Revision of the family Listropsoralgidae Fain, 1965 (Acariformes: Sarcoptoidea)-skin parasites of marsupials and rodents.

    Science.gov (United States)

    Bochkov, Andre V; Oconnor, Barry M; Grootaert, Patrick

    2013-01-01

    The family Listropsoralgidae Fain, 1965 (Acariformes: Sarcoptoidea) is represented by the permanent skin ectoparasites associated with the South American and Australian marsupials (12 species) and the South American rodents of the family Echimyidae (1 species). The phylogenetic relationships of these mites (12 ingroup and 2 outgroup species) are reconstructed on the basis of the maximum parsimony (MP) and Bayesian analyses (BA) of 76 morphological characters. MP analysis confirmed monophyly of the listropsoralgid genera, the strict consensus of 18 trees generated by MP has the following pattern: Petauralges (Listropsoralgoides, Didelphialges, Listropsoralges) with poor resolution among species of the genus Listropsoralges. The same tree was generated by BA. Both successive and implied weighting strategies resulted in 7 MP trees: Petauralges (Listropsoralgoides (Didelphialges (Listropsoralges))). The relationships between species of the genus Listropsoralges received the poorest resolution: L. caenolestes (L. monodelphis, L. vossi, L. faini, L. brevisetosa (L. thylamys (L. marmosa-L. caluromys))). The host-parasite relationships of listropsoralgids are briefly discussed. The family Listropsoralgidae is taxonomically revised and to date includes 13 species in 4 genera. Six species and one genus are described as new: Listropsoralges brevisetosus sp. n. from Marmosa murina (Didelphimorphia: Didelphidae) from Peru, Listropsoralges similis sp. n. from Caluromys derbianus (Didelphidae) from Panama, Listropsoralges thylamys sp. n. from Thylamys venustus (Didelphidae) from Bolivia, Listropsoralges vossi sp. n. from Monodelphis domestica (Didelphidae) from Brazil, Listropsoralges caenolestes sp. n. from Caenolestes fuliginosus (Paucituberculata: Caenolestidae) from Ecuador, and Didelphialges metachirus gen. n., sp. n. from Metachirus nudicaudatus (Didelphidae) from Peru. The female of Listropsoralges faini Bochkov and Wauthy, 2009 is described for the first time.

  4. Los marsupiales (Mammalia del Mioceno Superior de la Formación Cerro Azul (Provincia de La Pampa, Argentina

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    Visconti, G.

    2000-04-01

    Full Text Available We describe the most complete South American marsupial association of Huayquerian Age (late Miocene. Specimens were recovered from several new localities of central and northern La Pampa province (central Argentina, at levels assignable to Cerro Azul Fm.: Bajo Giuliani, Quehué, Telén, El Guanaco, and Laguna Chillhué. Loessoid sediments studied from this formation are indicative of lacustrine deposits overlaid by eolian levels bearing evidences of pedogenesis. A study of these levels at each one of the new localities led to their correlation in an integrated profile of Cerro Azul Fm. This formation corresponds to «Epecuén Fm.», at least in Salinas Grandes de Hidalgo, and probably also to the upper levels of Arroyo Chasicá Fm. The studied marsupials are representative of almost all major lineages (orders of South American Neogene marsupials. The marmosine didelphid Zygolestes tatei sp. nov. differs from the type species of the genus in its larger size, unreduced third lower premolar, and in the less reduction of the metaconid in the last lower molar. Another marmosine, Thylamys pinei sp. nov., differs from other Marmosini in the twinning of the para- and metaconid in the lower molars, and in the wider talonid of the m4. The Monodelphini marmosines Thylatheridium hudsoni y T. dolgopolae are abundant in several localities of this formation; their study confirms close affinities between this genus and Monodelphis. The didelphines Hyperdidelphys pattersoni and an indeterminate species of Lutreolina are also represented by a few specimens. A mandibular fragment including part of the last molar may represent the oldest record of a Sparassocynidae in central Argentina. The Borhyaenidae and Thylacosmilidae (Sparassodonta are also recorded by a few, fragmentary specimens. Pliolestes venetus sp. nov. (Paucituberculata, Caenolestidae differs from the type species of the genus in its smaller size and in the larger, less displaced metaconid in the