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Sample records for pulvinus

  1. Cell wall and enzyme changes during the graviresponse of the leaf-sheath pulvinus of oat (Avena sativa)

    Science.gov (United States)

    Gibeaut, David M.; Karuppiah, Nadarajah; Chang, S.-R.; Brock, Thomas G.; Vadlamudi, Babu; Kim, Donghern; Ghosheh, Najati S.; Rayle, David L.; Carpita, Nicholas C.; Kaufman, Peter B.

    1990-01-01

    The graviresponse of the leaf-sheath pulvinus of oat (Avena sativa) involves an asymmetric growth response and asymmetric processes involving degradation of starch and cell wall synthesis. Cellular and biochemical events were studied by investigation of the activities of related enzymes and changes in cell walls and their constituents. It is suggested that an osmotic potential gradient acts as the driving factor for growth, while wall extensibility is a limiting factor in pulvinus growth.

  2. Growth dynamics and cytoskeleton organization during stem maturation and gravity-induced stem bending in Zea mays L

    Science.gov (United States)

    Collings, D. A.; Winter, H.; Wyatt, S. E.; Allen, N. S.; Davies, E. (Principal Investigator)

    1998-01-01

    Characterization of gravitropic bending in the maize stem pulvinus, a tissue that functions specifically in gravity responses, demonstrates that the pulvinus is an ideal system for studying gravitropism. Gravistimulation during the second of three developmental phases of the pulvinus induces a gradient of cell elongation across the non-growing cells of the pulvinus, with the most elongation occurring on the lower side. This cell elongation is spatially and temporally separated from normal internodal cell elongation. The three characterized growth phases in the pulvinus correspond closely to a specialized developmental sequence in which structural features typical of cells not fully matured are retained while cell maturation occurs in surrounding internodal and nodal tissue. For example, the lignification of supporting tissue and rearrangement of transverse microtubules to oblique that occur in the internode when cell elongation ceases are delayed for up to 10 d in the adjacent cells of the pulvinus, and only occurs as a pulvinus loses its capacity to respond to gravistimulation. Gravistimulation does not modify this developmental sequence. Neither wall lignification nor rearrangement of transverse microtubules occurs in the rapidly elongating lower side or non-responsive upper side of the pulvinus until the pulvinus loses the capacity to bend further. Gravistimulation does, however, lead to the formation of putative pit fields within the expanding cells of the pulvinus.

  3. Contribución al estudio de los Hyphomycetes de España. III

    OpenAIRE

    Calvo Torras, Ma. de los Ángeles

    1981-01-01

    Se describen cuatro especies de Aspergillus: Aspergillus flavo-furcatis Batista et Maia, Aspergillus pulvinus Kwon et Fennell, Aspergillus ustus (Bainier) Thom et Church y Aspergillus conjunctus Kwon et Fennell. Description of four species of Aspergillus are presented: Aspergillus flavo-furcatis Batista et Maia, Aspergillus pulvinus Kwon et Fennell, Aspergillus ustus (Bainier) Thom et Church and Aspergillus conjunctus Kwon et Fennell.

  4. Light-driven movements of the trifoliate leaves of bean (Phaseolus vulgaris L.). Spectral and functional analysis

    International Nuclear Information System (INIS)

    Koller, D.; Ritter, S.; Fork, D.C.

    1996-01-01

    The light-driven responses of the terminal leaflet of bean were analyzed spectrally and functionally. Laminar elevation increases rapidly in response to continuous overhead exposure of its pulvinus to blue light. This response is enhanced in its early stages by simultaneous exposure to red light. The pulvinus responds similarly to continuous overhead unmixed red, or far-red light, albeit at much lower rates. The response to overhead red, alone, or during enhancement of the response to blue, was not affected by simultaneous far-red. However, the response to blue alone, or enhanced by mixture with red, was partially inhibited by simultaneous exposure to far-red. The results suggest that the response to blue resulted mostly from a blue-absorbing pigment system, but may involve some absorption by phytochrome, while responses to red or far-red, with and without blue, may be mediated by high-irradiance responses of phytochrome. Functional differences between the responses to red and blue become apparent when the abaxial (lower), or lateral sectors of the pulvinus are exposed to them, separately and in combination. These differences suggest that red controls the photonastic unfolding of the pulvinus, whereas blue controls its phototropic responses. These responses co-exist in the same tissue, but are separate and additive. (author)

  5. Statistical analysis of general, clinical and radiographic parameters of navicular disease in the horse

    International Nuclear Information System (INIS)

    Langfeldt, N.; Hertsch, B.

    1988-01-01

    With 20,4 % the syndrome navicular disease has a remarkable part of lameness in the equine fore limb. Although intensive investigations of the last years, there is no uniform opinion in the clinical diagnosis of navicular disease. At first there is a differential description of the diagnosis of navicular disease and a presentation of the importance of this disease from the whole patients of the equine hospital of the Tierärztliche Hochschule Hannover about five years (1980-1984). After that, the importance of the identification of pain with pain provocation test and the elimination of pain by anesthetic nerve blocking are described. The result of the anesthetic block of the ''Ramus pulvinus'' of the medial and lateral palmar digital nerves is a necessary part in clinical diagnosis of navicular disease [de

  6. Plant Type and Its Effects on Canopy Structure at Heading Stage in Various Ecological Areas for a Two-line Hybrid Rice Combination, Liangyoupeijiu

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    Chuan-gen LU

    2010-09-01

    Full Text Available A two-line hybrid rice combination, Liangyoupeijiu, was used to estimate several factors of plant type, and environmental models for these factors at the heading stage were established using the data of eight ecological experimental sites in 2006 and 2007. According to climatic data from 1951 to 2005, the differences in those factors and their effects on plant canopy were analyzed for four rice cropping areas in China, including South China, the middle-lower reaches of the Yangtze River, Sichuan Basin, and river valley in Yunnan, China. The thickness of leaf layer (the distance from pulvinus of the third leaf from the top to the tip of flag leaf and distribution of leaf area could be used as candidate indices for the plant type of a rice canopy.

  7. Taxonomic value of foliar characters in Dahlstedtia Malme: Leguminosae, Papilionoideae, Millettieae Valor taxonômico de caracteres foliares em Dahlstedtia Malme: Leguminosae, Papilionoideae, Millettieae

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    Simone de Pádua Teixeira

    2006-06-01

    Full Text Available Dahlstedtia Malme (Leguminosae is a neotropical genus, native to the Brazilian Atlantic Forest, and comprises two species, D. pinnata (Benth. Malme and D. pentaphylla (Taub. Burk., although it has been considered a monotypic genus by some authors. Leaf anatomy was compared to verify the presence of anatomical characters to help delimit species. Foliar primordium, leaflet, petiolule, petiole and pulvinus were collected from cultivated plants (Campinas, SP, Brazil and from natural populations (Picinguaba, Ubatuba and Caraguatatuba, SP, Brazil - D. pinnata; Antonina, PR, Brazil - D. pentaphylla. Studies on leaflet surface assessment (Scanning Electron Microscopy, as well as histology and venation analyses were carried out of dehydrated, fresh and fixed material from two species. Leaflet material was macerated for stomatal counts. Histological sections, obtained by free-hand cut or microtome, were stained with Toluidine Blue, Safranin/Alcian Blue, Ferric Chloride, Acid Phloroglucin. Secretory cavities are present in the lamina, petiolule, petiole, pulvinus and leaf primordium in D. pentaphylla, but not in D. pinnata, and can be considered an important character for species diagnosis. Other leaf characters were uninformative in delimiting Dahlstedtia species. There is cambial activity in the petiolule, petiole and pulvinus. This study, associated with other available data, supports the recognition of two species in Dahlstedtia.Dahlstedtia Malme (Leguminosae é um gênero neotropical, com duas espécies reconhecidas, D. pinnata (Benth. Malme e D. pentaphylla (Taub. Burk., embora tenha sido considerado monotípico por alguns autores. Seus representantes ocorrem na Floresta Atlântica, nos Estados do Sul e Sudeste do Brasil. Neste trabalho, realizamos um estudo comparativo da anatomia foliar, para verificar a presença de caracteres que possam auxiliar a identificação das espécies. Primórdio foliar, lâmina foliar, peciólulo, pecíolo e pulvino

  8. Morfologia e anatomia foliar de Bauhinia curvulha Benth. (Leguminosae-Caesalpinioideae Morphology and anatomy of Bauhinia curvula Benth. (Leguminosae-Caesalpinoideae

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    Maria Helena Rezende

    1994-07-01

    Full Text Available Foi realizado o estudo morfológico e anatômico da folha de Bauhinia cumula Benth., espécie de cerrado. As observações foram feitas em folhas adultas, tratadas segundo a metodologia usual utilizada em anatomia vegetal. Foi observado que a espécie apresenta as seguintes características: folhas bilobadas cuja incisão foliar chega próximo à região motora; um par de estipulas membranáceas; um par de nectários extraflorais, localizadaos na base do pulvino proximal; a venação possui padrão acródomo; o pecíolo, que possui dois pulvinos, um proximal e um distai, apresenta epiderme contendo grande quantidade de tricomas tecto res simples e glândulas; a lâmina foliar é anfiestomática com predomínio de estômatos dos tipos anomocítico e paracítico; a epiderme adaxial é monoestratificada, subpapilosa, desprovida de tricomas tectores simples e glândulas; a epiderme abaxial é subpapilosa, apresentando numerosos tricomas tectores simples e glândulas; e o mesofilo é formado predominantemente por parênquima paliçádico.A morphological and anatomical study of Bauhinia curvula Benth. leaf, a cerrado spe-cies, was perfomed. The observations, in grown up leaves, prepared according to the costumary methodology used in plant anatomy, showed the following characteristics of the species: bilobed leaves with foliar incision close to the motor region; one pair of membranaceous stipules; one pair of extrafloral nectaries located on the basis of the proximal pulvinus; acrodromous patterns of leaf venetion; the petiole, which has two pulvinus, one proximal and one distal, has an epidermis containing large quantities of simple tector trichomes and glands; the leaf blade, amphiestomatic, with predominance of anomocytic and paracytic stomata; the adaxial epidermis uniserial, sub papillose, without tector trichomes and glands; the abaxial epiderms, sub-papillose, presents a high number of simple trichomes and glands; and the mesophyll with a basic

  9. Genome-Wide Identification, Evolutionary Analysis and Expression Profiles of LATERAL ORGAN BOUNDARIES DOMAIN Gene Family in Lotus japonicus and Medicago truncatula.

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    Tianquan Yang

    Full Text Available The LATERAL ORGAN BOUNDARIES DOMAIN (LBD gene family has been well-studied in Arabidopsis and play crucial roles in the diverse growth and development processes including establishment and maintenance of boundary of developmental lateral organs. In this study we identified and characterized 38 LBD genes in Lotus japonicus (LjLBD and 57 LBD genes in Medicago truncatula (MtLBD, both of which are model legume plants that have some specific development features absent in Arabidopsis. The phylogenetic relationships, their locations in the genome, genes structure and conserved motifs were examined. The results revealed that all LjLBD and MtLBD genes could be distinctly divided into two classes: Class I and II. The evolutionary analysis showed that Type I functional divergence with some significantly site-specific shifts may be the main force for the divergence between Class I and Class II. In addition, the expression patterns of LjLBD genes uncovered the diverse functions in plant development. Interestingly, we found that two LjLBD proteins that were highly expressed during compound leaf and pulvinus development, can interact via yeast two-hybrid assays. Taken together, our findings provide an evolutionary and genetic foundation in further understanding the molecular basis of LBD gene family in general, specifically in L. japonicus and M. truncatula.

  10. Análise morfoanatômica comparativa da folha de Bauhinia forficata Link e B. variegata Linn. (Leguminosae, Caesalpinioideae Comparative morphogical and anatomycal analyses of Bauhinia forficata Link and B. variegata Linn. (Leguminosae, Caesalpinioideae leaves

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    Makeli Garibotti Lusa

    2009-03-01

    Full Text Available Esse trabalho foi desenvolvido com o propósito de subsidiar o controle de qualidade das espécies medicinais Bauhinia forficata Link e B. variegata Linn. Essas foram coletadas em jardins e terrenos baldios de Curitiba, Paraná, Brasil. As amostras do limbo, pecíolo e pulvino foram fixadas em F.A.A. 50 e conservadas em etanol 70%. O seccionamento do material foi feito em micrótomo de rotação (material incluído em historresina ou a mão livre e as lâminas foram montadas de forma permanente ou semipermanente. Foram realizadas análises em microscopia fotônica e eletrônica de varredura. A folha de B. forficata é alongada, com folíolos unidos em torno da metade do limbo, ápices agudos, superfície adaxial lisa e mucro entre os folíolos. Enquanto que, B. variegata possui folha mais larga que longa, com folíolos unidos na porção terminal do limbo e ápices obtusos. Nos pulvinos de B. variegata ocorrem camadas de colênquima, ausentes em B. forficata. O formato e a bainha de fibras dos pecíolos, em secção transversal, são distintos entre as espécies, assim como a distribuição dos estômatos e tricomas no limbo e a forma do bordo em secção transversal. B. variegata possui maior quantidade de idioblastos com drusas e compostos fenólicos. As características morfológicas e anatômicas de B. forficata e B. variegata contribuem para a identificação e diferenciação das espécies, sendo importantes para o controle de qualidade do material destinado à pesquisa e à indústria farmacêutica.This work has been developed with the purpose of helping the quality control of the medicinal species Bauhinia forficata Link and B. variegata Linn., which were collected in gardens and vacant lots in Curitiba, Paraná, Brazil. The samples of leaf blade, petiole and pulvinus were fixed in FAA 50 and preserved in alcohol 70. The sectioning of the material was made in rotational microtome (with the material included in historesine or manually and

  11. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of [3]gibberellin A

    International Nuclear Information System (INIS)

    Rood, S.B.; Kaufman, P.B.; Abe, H.; Pharis, R.P.

    1987-01-01

    [ 3 H]Gibberellin A 20 (GA 20 ) of high specific radioactivity was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the [ 3 H]GA 1 - and [ 3 H]GA 29 -like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of [ 3 H]GA 1 [ 3 H]GA 29 , and [ 3 H]GA 8 . The tentative identification of these putative [ 3 H]GA glucosyl conjugates was further supported by the release of the free [ 3 H]GA moiety after cleavage with cellulase. Within 12 hours of the [ 3 H]GA 20 feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheaf pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of [ 3 H]GA 20 , especially [ 3 H] GA 1 , in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the Tanginbozu dwarf rice microdroassay. Lower halves contained higher total levels of GA-like activity

  12. Gross Anatomy of Pampas Deer (Ozotoceros bezoarticus, Linnaeus 1758) Mouth and Pharynx.

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    Pérez, W; Vazquez, N; Ungerfeld, R

    2017-04-01

    The aims of this study were to describe the anatomy of the mouth and pharynx of the pampas deer, and to consider its evolutionary feeding niche according to those characteristics. Gross dissections of the mouth and pharynx were performed in 15 animals, 10 adult females and five young animals under 1 year (three males and two females), all dead by causes unrelated to this anatomical region. The upper lip entered in the constitution of a pigmented nasolabial plane. The masseter muscles weighed 43.8 ± 3.5 g and represented 0.23% of body weight, which corresponds to ruminants of feeders intermediate to grazers and browsers. Parotid glands represented 0.08% of the body weight, characteristic that also categorize the pampas deer as belonging to the intermediate feeding group. The dental formula was the same of the domestic ruminants. The upper incisors and canines were absent, and instead of them, there was a dental pad (Pulvinus dentalis). The upper canine teeth were present only in the deciduous dentition. The existence of a brachydont dentition turns Ozotoceros very vulnerable to continuous use as there is no compensatory teeth growth. The particular anatomy of the mouth and lips of this animal was adapted to a very selective feeding, taking highly nutritious sprouts beyond plant category. In conclusion and in addition to previous studies of anatomy of the digestive organs in this species, pampas deer may be categorized as belonging to the intermediate type of feeding. © 2016 Blackwell Verlag GmbH.

  13. Cytoplasmic pH dynamics in maize pulvinal cells induced by gravity vector changes

    Science.gov (United States)

    Johannes, E.; Collings, D. A.; Rink, J. C.; Allen, N. S.; Brown, C. S. (Principal Investigator)

    2001-01-01

    In maize (Zea mays) and other grasses, changes in orientation of stems are perceived by pulvinal tissue, which responds to the stimulus by differential growth resulting in upward bending of the stem. The amyloplast-containing bundle sheath cells are the sites of gravity perception, although the initial steps of gravity perception and transmission remain unclear. In columella cells of Arabidopsis roots, we previously found that cytoplasmic pH (pH(c)) is a mediator in early gravitropic signaling (A.C. Scott, N.S. Allen [1999] Plant Physiol 121: 1291-1298). The question arises whether pH(c) has a more general role in signaling gravity vector changes. Using confocal ratiometric imaging and the fluorescent pH indicator carboxy seminaphtorhodafluor acetoxymethyl ester acetate, we measured pH(c) in the cells composing the maize pulvinus. When stem slices were gravistimulated and imaged on a horizontally mounted confocal microscope, pH(c) changes were only apparent within the bundle sheath cells, and not in the parenchyma cells. After turning, cytoplasmic acidification was observed at the sides of the cells, whereas the cytoplasm at the base of the cells where plastids slowly accumulated became more basic. These changes were most apparent in cells exhibiting net amyloplast sedimentation. Parenchyma cells and isolated bundle sheath cells did not show any gravity-induced pH(c) changes although all cell types responded to external stimuli in the predicted way: Propionic acid and auxin treatments induced acidification, whereas raising the external pH caused alkalinization. The results suggest that pH(c) has an important role in the early signaling pathways of maize stem gravitropism.

  14. The micromorphology of the blesbuck louse Damalinia (Damalinia crenelata as observed under the scanning electron microscope

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    M.L. Turner

    2003-12-01

    Full Text Available The blesbuck is an important game animal on many game farms and reserves in South Africa. Damalinia crenelata, a biting louse, host-specific to the blesbuck, feed upon epidermal debris of this antelope, leading to severe skin irritation and dermatitis. Symptomatic scratching by the host aggravates these conditions. High infestations may lead to decreased population numbers. Live lice were collected from a blesbuck in the Rietvlei Nature Reserve and prepared for selectron microscopic investigation. Micrographs were recorded. The SEM investigation revealed several micromorphological features not previously described in D. crenelata. Besides the obvious anatomical differences in the reproductive organs of the male and female, several other differences were noted. The antennal flagellae showed morphological differences as well as certain features on the ventral surfaces of the head. Dorsally the forehead was markedly emarginated and showed an acute invagination (clypeo labral suture in the pulvinal area. The ventral surface of the head clearly demonstrated the structures of the preantennal regions such as ventral carina, pulvinus, labrum, mandibles and clypeus. The epipharynx appeared as an underlying extension of the labrum. The rims of the clypeus were more raised and thickened in the female than in that of the male. The mandibles were not notched and were noted to be angular in shape. The three segments of each of the antennae of the male were thicker and more robust than than those of the female. This could suggest sexual dimorphism in this species. The sensilla basoconica comprised 10 pegs. Pit organs were seen within the pore organs. The prothorax and mesothorax were clearly distinguished. The abdominal segments showed six pairs of spiracles. The male andfemale terminalia were confirmed to be strongly sexually dimorphic. The three pairs oflegs each terminated in a single, long and slender, claw.

  15. Gibberellins and gravitropism in maize shoots: endogenous gibberellin-like substances and movement and metabolism of [3H]Gibberellin A20

    Science.gov (United States)

    Rood, S. B.; Kaufman, P. B.; Abe, H.; Pharis, R. P.

    1987-01-01

    [3H]Gibberellin A20 (GA20) of high specific radioactivity (49.9 gigabecquerel per millimole) was applied equilaterally in a ring of microdrops to the internodal pulvinus of shoots of 3-week-old gravistimulated and vertical normal maize (Zea mays L.), and to a pleiogravitropic (prostrate) maize mutant, lazy (la). All plants converted the [3H]GA20 to [3H]GA1- and [3H]GA29-like metabolites as well as to several metabolites with the partitioning and chromatographic behavior of glucosyl conjugates of [3H]GA1, [3H]GA29, and [3H]GA8. The tentative identification of these putative [3H]GA glucosyl conjugates was further supported by the release of the free [3H]GA moiety after cleavage with cellulase. Within 12 hours of the [3H]GA20 feed, there was a significantly higher proportion of total radioactivity in lower than in upper halves of internode and leaf sheath pulvini in gravistimulated normal maize. Further, there was a significantly higher proportion of putative free GA metabolites of [3H]GA20, especially [3H]GA1, in the lower halves of normal maize relative to upper halves. The differential localization of the metabolites between upper and lower halves was not apparent in the pleiogravitropic mutant, la. Endogenous GA-like substances were also examined in gravistimulated maize shoots. Forty-eight hours after gravistimulation of 3-week-old maize seedlings, endogenous free GA-like substances in upper and lower leaf sheath and internode pulvini halves were extracted, chromatographed, and bioassayed using the "Tanginbozu" dwarf rice microdrop assay. Lower halves contained consistently higher total levels of GA-like activity. The qualitative elution profile of GA-like substances differed consistently, upper halves containing principally a GA20-like substance and lower halves containing principally a GA20-like substance and lower halves containing mainly GA1-like and GA19-like substances. Gibberellins A1 (10 nanograms per gram) and A20 (5 nanograms per gram) were identified

  16. An Annotated And Illustrated Catalogue Of Polypores (Agaricomycetes Of The Białowieża Forest (NE Poland

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    Karasiński Dariusz

    2015-12-01

    Full Text Available The Białowieża Forest (BF is one of the best-preserved lowland deciduous and mixed forest complexes in Europe, rich in diverse fungi. This paper summarizes what is known about the poroid fungi of the Polish part of the Białowieża Forest, based on literature data, a re-examination of herbarium materials, and the authors’ studies from 1990–2014. An annotated catalogue of polypores recorded in the forest is presented, including 80 genera with 210 species. All literature and herbarium records are enumerated, and 160 species are illustrated with color pictures. Fourteen species previously reported in the literature have uncertain status because they lack voucher specimens and were not confirmed in recent field studies. Antrodiella subradula (Pilát Niemelä & Miettinen, previously known from Asia, is reported for the first time from Europe. Fourteen species are newly reported from the Białowieża Forest (mainly from Białowieża National Park, including 8 species with first records in Poland (Antrodia hyalina Spirin, Miettinen & Kotir., Antrodia infirma Renvall & Niemelä, Antrodiella subradula, Junghuhnia fimbriatella (Peck Ryvarden, Postia folliculocystidiata (Kotl. & Vampola Niemelä & Vampola, Postia minusculoides (Pilát ex Pilát Boulet, Skeletocutis chrysella Niemelä, Skeletocutis papyracea A. David, and 6 species reported previously from other localities in Poland [Antrodiella faginea Vampola & Pouzar, Dichomitus campestris (Quél. Domański & Orlicz, Loweomyces fractipes (Berk. & M. A. Curtis Jülich, Oxyporus latemarginatus (Durieu & Mont. Donk, Perenniporia narymica (Pilát Pouzar, Phellinus nigricans (Fr. P. Karst.]. Several very rare European polypores already reported from the Białowieża Forest in the 20th century, such as Antrodia albobrunnea (Romell Ryvarden, Antrodiella foliaceodentata (Nikol. Gilb. & Ryvarden, Buglossoporus pulvinus (Pers. Donk, Dichomitus albidofuscus (Domański Domański and Gelatoporia subvermispora