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The loricate choanoflagellate genera Pleurasiga and Parvicorbicula are taxonomically ambiguous. Pleurasiga because of the uncertainty that relates to the true identity of the type species, and Parvicorbicula because too many newly described species over time have been dumped here in lack of better options. While all species currently allocated to the genus Pleurasiga (with the exception of the type species) are observed in our samples from the global warm water belt, the genus Parvicorbicula is represented by just a few and mostly infrequently recorded taxa. Two new species, viz. Pl. quadrangiella sp. nov. and Pl. minutissima sp. nov., are described here. While the former is closely related to Pl. echinocostata, the latter is reminiscent of Pl. minima. Core species of Pleurasiga and Parvicorbicula deviate from the vast majority of loricate choanoflagellates in having both the anterior and the mid-lorica transverse costae located exterior to the longitudinal costae. In Pl. quadrangiella there is no mid-lorica transverse costa but rather a small posterior transverse costa located inside the longitudinal costae. In Pl. minutissima the mid-lorica transverse costa has extensive costal strip overlaps which reveal patterns of costal strip junctions that deviate from the norm.  相似文献   

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The main outcome of this and subsequent papers is to provide a baseline survey of heterotrophic protist diversity from warm water marine ecosystems, exemplified by loricate choanoflagellates (Acanthoecida). Genera in focus here (i.e. Bicosta, Apheloecion, Campyloacantha, Crucispina, Calliacantha and Saroeca) possess anterior spines or projections and a posterior pedicel, and have 0, 1 or 2 transverse costae. Longitudinal costae are, with the exception of Campyloacantha, external to transverse costal elements across all genera examined here. We describe here Apheloecion eqpacia sp. nov. and Calliacantha magna sp. nov., both of which are so far distributionally confined to warm water habitats. A ‘form A’ of Bicosta minor is introduced to facilitate the distinction between B. minor sensu stricto and a presumed warm water adapted variant with a posterior lorica chamber twist of the longitudinal costae.  相似文献   

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The tectiform loricate choanoflagellate genera Calotheca, Stephanacantha and Syndetophyllum have all been first described from warm water habitats and share the presence of flattened and often elaborate costal strips in the lorica. The current reinvestigation does confirm both the widespread occurrence of these taxa within the global warm water belt, and largely corroborates the established genus and species matrix. We describe here Stephanacantha oceanica sp. nov. which closely resembles S. campaniformis, and transfer Parvicorbicula zigzag to the genus Stephanacantha, despite differences in costal strip morphology, but based on a complete agreement in lorica constructional details.  相似文献   

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The ambition to generate an overview of warm water loricate choanoflagellate biodiversity, based on a classic morphometric approach, is here completed by analyses of a range of tiny forms with anterior spines or projections and in most cases also a posterior pedicel. The warm water study complements previously obtained results from the more extensively studied temperate and polar regions of the world’s oceans. It thus contributes to a significantly more balanced approach to global diversity patterns for these organisms. The current survey includes taxa such as Polyfibula elatensis, Parvicorbicula pedicellata, as well as a range of primarily undescribed and taxonomically challenging species, that are in an interim approach allocated to Coronoeca gen. nov. (C. kosmaniae sp. nov., C. conicella sp. nov., C. superpositus (Booth) comb. nov., C. marchantii sp. nov., C. tongiae sp. nov., and C. patongiensis sp. nov.). The analysis of warm water acanthoecid biodiversity has revealed in total 80 species from the six geographic regions sampled, corresponding to approximately 50% of all loricate species described. Nineteen species are previously undescribed forms. The Andaman Sea, Thailand, and West Australia are in a global context the most species-rich regions with 62 and 64 species respectively.  相似文献   

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Keraunea Cheek & Simão‐Bianchini gen. nov. (Convolvulaceae) from Brazil is described and illustrated as the third known neuropeltoid genus. It appears allied to the Old World genera of Neuropeltis Wall and Neuropeltopsis Ooststr. in having wind‐dispersed fruits not by enlarged sepals, but subtended by an enlarged papery bract to which the pedicel is adnate, and flowers in which the bracteoles are absent or usually very inconspicuous. Keraunea brasiliensis, the single species thus far known, is here assessed as ‘Endangered’.  相似文献   

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Three species of loricate choanoflagellates (Choanoflagdlida,Acanthoecidae), collected from the Andaman Sea near Phuket Island(SW Thailand), have been described and referred to Apheloeciongen.nov. (holotype: A. quadrispinum sp.nov.). All species possessa single-chambered lorica composed of one transverse costs overlaidby a limited number of longitudinal costae which converge posteriorly.Anteriorly the longitudinal costae protrude above the transversecosta as sharp pointed spines. In A. quadrispinum sp.nov. andA. pentacanthum sp.nov. the lorica is terminated by a shortposterior spine, whereas in A. articulatum sp.nov. the pedicelis much more prominent, consisting of several costal stripswhich are joined end-to-end. The species of Apheloecion appearto be most closely related to species of Calliacantha and Monocosta.None of the species described are so far known from localitiesoutside the Andaman Sea.  相似文献   

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Summary The loricate choanoflagellate Bicosta spinifera was observed frequently in Antarctic samples collected along Scotia/Weddell Sea transects. The entire population showed a conspicuous bimodal size distribution. Large forms were predominant in Scotia Sea samples, while only small specimens were found in the Confluence area. Prior to cell division Bicosta spinifera produces a complete set of costal strips in a temporary tail-like protrusion. Small specimens sometimes possess a tail similar to that found in large specimens. The fact that B. spinifera may increase considerably in size following cell division, in connection with the finding of aberrant minute forms, have prompted us to hypothesize a polymorphic life history in B. spinifera. The term caudiform division is introduced to describe division in B. spinifera. Saroeca attenuata also produces a tail prior to cell division, but is otherwise shown to undergo a mixed caudiform/tectiform type of division.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundatin  相似文献   

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The new genusBotryozyma with a single species,B. nematodophila is proposed for two isolates from nematodes (Panagrellus zymosiphilus) occurring in grapes with sour-rot. The new genus has typical ascomycetous characteristics and, being unable to produce ascospores, is placed in the family Candidaceae.  相似文献   

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Wajira albescens Thulin (Leguminosae–Papilionoideae–Phaseoleae–Phaseolinae) is described as a new monotypic genus confined to the arid bushlands of E Kenya.  相似文献   

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A multi‐gene (SSU, LSU, psbA, and COI) molecular phylogeny of the family Corallinaceae (excluding the subfamilies Lithophylloideae and Corallinoideae) showed a paraphyletic grouping of six monophyletic clades. Pneophyllum and Spongites were reassessed and recircumscribed using DNA sequence data integrated with morpho‐anatomical comparisons of type material and recently collected specimens. We propose Chamberlainoideae subfam. nov., including the type genus Chamberlainium gen. nov., with C. tumidum comb. nov. as the generitype, and Pneophyllum. Chamberlainium is established to include several taxa previously ascribed to Spongites, the generitype of which currently resides in Neogoniolithoideae. Additionally we propose two new genera, Dawsoniolithon gen. nov. (Metagoniolithoideae), with D. conicum comb. nov. as the generitype and Parvicellularium gen. nov. (subfamily incertae sedis), with P. leonardi sp. nov. as the generitype. Chamberlainoideae has no diagnostic morpho‐anatomical features that enable one to assign specimens to it without DNA sequence data, and it is the first subfamily to possess both Type 1 (Chamberlainium) and Type 2 (Pneophyllum) tetra/bisporangial conceptacle roof development. Two characters distinguish Chamberlainium from Spongites: tetra/biasporangial conceptacle chamber diameter (<300 μm in Chamberlainium vs. >300 μm in Spongites) and tetra/bisporangial conceptacle roof thickness (<8 cells in Chamberlainium vs. >8 cells in Spongites). Two characters also distinguish Pneophyllum from Dawsoniolithon: tetra/bisporangial conceptacle roof thickness (<8 cells in Pneophyllum vs. >8 cells in Dawsoniolithon) and thallus construction (dimerous in Pneophyllum vs. monomerous in Dawsoniolithon).  相似文献   

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Dianyuea C. Shang, S. Liao & Z. X. Zhang, a new monotypic genus of Salicaceae based on Flacourtia turbinata H. J. Dong & H. Peng, is described and illustrated. Morphologically, Dianyuea differs from Flacourtia Comm. ex L'Hér. by having six connate stamens, basal placentation and lobed seed appendages. All those features indicate that Dianyuea is allied with Scyphostegia Stapf. A molecular phylogenetic analysis using plastid trnL‐F, matK, and rbcL sequence data for representatives of 16 genera in Salicaceae s.l. shows that Dianyuea is sister to Scyphostegia. The new combination Dianyuea turbinata (H. J. Dong & H. Peng) C. Shang, S. Liao & Z. X. Zhang is proposed.  相似文献   

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《Mycoscience》2020,61(5):240-248
Taxonomic studies including morphological observations and phylogenetic analyses were conducted on Japanese “uragin-take”, an unidentified species from Amazonia, Brazil and their allies. Phylogenetic analyses using ITS, nrLSU and RPB2 regions revealed that “uragin-take”, Neofomitella polyzonata and the unidentified species formed a monophyletic clade separate from the clade including the other four Neofomitella spp. and that “uragin-take” is conspecific with N. polyzonata. Morphological investigations on authentic specimens revealed that Polyporus subradiatus is a prior name for N. polyzonata. We propose Hirticrusta gen. nov. typified by H. subradiata segregated from Neofomitella, and we erected H. amazonica sp. nov. for the unidentified species. Hirticrusta is characterized by annual to biennial and sessile basidiocarps, semicircular to dimidiate pileus, velutinous to tomentose hairs on pileus surface, buff to brown context with a crustose layer indicated by a dark brown line forming a longitudinal section below the superficial hairs, a trimitic hyphal system, crustose layer composed of parallel and densely arranged brown hyphae and cylindrical basidiospores. The new species, H. amazonica is distinguishable from other polypores by downy and long tomentum on the pileus surface (up to 20 mm thick), brown context with a dark brown layer below the tomentum and round pores (5–7/mm).  相似文献   

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In Iceland, the examination of whooper swans (Cygnus cygnus L.) viscera resulted in the detection of adult digenean flukes of the family Schistosomatidae. The mature worms occurring in the blood vessels of the large intestine and mesenterium caused vascular lesions, around the eggs deposited in the intestinal mucosa and liver granulomatous reactions developed. The morphology of the isolated schistosomes shows certain similarity with the flukes of the genus Trichobilharzia; in males reduced gynecophoral canal, and on both sexes both suckers and spatulate ends are present. However, the Icelandic flukes possess other morphological features which are distinct from the genus: the point of caecal reunion in males takes place posterior to gynecophoral canal and the genital pore is behind acetabulum and anterior to caecal reunion. In order to evaluate the identity of Icelandic schistosomes, sequencing of ITS region of DNA was performed, and the obtained sequence was deposited in GenBank under the accession no. DQ067561. Following phylogenetic analysis of relationship between the sequence of Icelandic flukes and database sequences of other bird schistosome genera (Trichobilharzia, Gigantobilharzia and Dendritobilharzia) showed different position of Icelandic worms in the phylogenetic tree. In conclusion, our study revealed new genus and species of schistosome flukes--Allobilharzia visceralis gen. et sp. n.  相似文献   

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