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1.
A new diatom (Bacillariophyceae) genus and two new species are described from the arid region of the North American southwest. The new genus, Playaensis, and new species, P. circumfimbria and P. furtiva, are distinguished by frustule morphology and autecology. Playaensis possesses unique, narrowly lunate longitudinal ribs bordering the raphe and spathulate spines, but their evolutionary relationship to known genera is unclear. In Payton Lake, New Mexico, P. circumfimbria and P. furtiva are rare in the diatom community, and their geographic and geological extent are not known, but they may be restricted to alkaline, slightly saline lakes of the region.  相似文献   

2.
Zingiber shuanglongensis sp.nov.is a species endemic to Taiwan,China,that has been found in Nantou and Kaohsiung.In this study,the new Zingiber species is illustrated and the results of morphological a...  相似文献   

3.
A new species of Cocconeis has been found growing on the green seaweed Caulerpa racemosa (Forsskål) J. Agardh var. laete‐virens (Montagne) Weber van Bosse from Shikine Island in the Izu Islands on the Pacific coast of Japan; we propose the name Cocconeis shiki‐nensis Hid. Suzuki and describe the species by light microscopy (LM) and electron microscopy (EM). This taxon was also collected from the plastic plates used for rearing in seed production systems of the abalone Nordotis discus hannai Ino and the horned turban Turbo cornutus Solander in the Toyama Prefectural Fisheries Research Institute facing the Sea of Japan. The main morphological features of C. shikinensis are as follows. The valves are elliptic. The valve face of the raphid valve (RV) is slightly concave and that of the araphid valve (AV) is complementary to the RV and convex. The single plastid is flat, C‐shaped and elaborately lobed. The raphe on the RV is straight. The each terminal area expands to both sides along the valve margin, forming an arrowhead‐shaped, thickened hyaline area. The striae consist of small, round areolae and are radiate and uniseriate. On the AV, the striae consist of several alveoli. Each alveolus opens internally by means of a circular foramen. The valvocopula of each valve is fimbriate and open. The cingulum attached to the AV consists of three girdle bands; a valvocopula and two bands (copula and pleura), which are open and have ligulae. The relationship between C. shikinensis and similar members of the genus Cocconeis is discussed.  相似文献   

4.
The canal-bearing diatom genus Nagumoea, described based on only morphological evidence, was tentatively assigned to the order Bacillariales, although its phylogenetic position remained unclear. Because three isolates of Nagumoea (SK002, SK024 and SK053) were successfully established from Japanese coasts, we performed their morphological observations and molecular phylogenetic analyses to discuss the phylogeny and taxonomic position of this genus. Strains SK002 and SK024 were identified as Nagumoea africana, whereas SK053 conformed with Nagumoea serrata. There was high interspecific divergence between N. africana and N. serrata in the rbcL sequences (8.03–8.17%), indicating their distinctness. Furthermore, intraspecific variations were detected within N. africana (2.35%) in the rbcL, implying its cryptic diversity. The maximum likelihood and Bayesian phylogenetic trees inferred from the plastid rbcL, psbC and nuclear 18S rDNA genes recovered Nagumoea as monophyletic with strong statistical support and embedded within an unresolved, poorly supported lineage containing Achnanthes, Craspedostauros, Staurotropis and Undatella in the canal-bearing order Bacillariales (= the family Bacillariaceae). Although the constrained tree based on the monophyly of Nagumoea and the other canal-bearing clade (Surirellales and Rhopalodiales) was statistically rejected by the topology tests, the phylogenetic position of Nagumoea with other Bacillarialean members remains equivocal. The possession of two plastids positioned fore and aft, observed in the present study, and lack of keel, typical of the Bacillariales, indicate the possibility of Nagumoea being part of the ingroup of the Bacillariales or its closely related outgroup.  相似文献   

5.
6.
Based on recent molecular phylogenetic studies, the Old World bat family Miniopteridae, composed of species in the genus Miniopterus , has been shown to contain complex paraphyletic species, many of which are cryptic based on convergent morphological characters. Herein we resolve the phylogenetic relationships and taxonomy of the species complex M . manavi on Madagascar and in the Comoro Archipelago, where these animals occur in different bioclimatic zones. First using mitochondrial cytochrome- b sequence data to define clades and then morphology to corroborate the molecular data, including comparisons to type specimens, we demonstrate that animals identified as this taxon are a minimum of three species: M . manavi sensu stricto occurs in at least the central portion of the Central Highlands; M . griveaudi has a broad distribution in lowland northern and central western Madagascar and the Comoros (Anjouan and Grande Comore), and M . aelleni sp. n. has been found in northern and western Madagascar and the Comoros (Anjouan). In each case, these three clades were genetically divergent and monophyletic and the taxa are diagnosable based on different external and craniodental characters. One aspect that helped to define the systematics of this group was isolation of DNA from one of the paratypes of M. manavi collected in 1896 and new topotypic material. Miniopterus manavi is most closely allied to a recently described species, M. petersoni . At several localities, M . griveaudi and M . aelleni have been found in strict sympatry, and together with M. manavi sensu stricto show considerable convergence in morphological characters, but are not immediate sister taxa. In defining and resolving the systematics of cryptic species, such as miniopterid bats, the process of defining clades with molecular tools, segregating the specimens accordingly, and identifying corroborative morphological characters has been notably efficient.  相似文献   

7.
In the present study, two abundant epiphytic diatom taxa were isolated from the assimilation hairs of the brown macroalga Chordaria flagelliformis collected in the Arctic Kongsfjorden (Spitsbergen, Norway), established as unialgal cultures and their growth rates determined under controlled photon fluence rate and temperature conditions. Using morphological (light and scanning electron microscopy) and SSU rRNA gene data both isolates (ROS D99 and ROS D125) were identified as members of a Fragilaria–Synedropsis clade. The molecular data of ROS D99 and ROS D125 were not identical to any other published sequence. While ROS D99 has been identified as Fragilaria barbararum mainly due to the SEM characteristics, ROS D125 could not be definitely identified although morphological data speak for Fragilaria striatula. Both diatom species showed similar growth rates at all temperatures and photon fluence rates tested. They grew well between 0 and 15°C with optimum temperatures of 12–14°C, but did not survive 20°C. Therefore, compared to Antarctic diatoms both taxa from Kongsfjorden can be characterised as eurythermal organisms. Increasing photon fluence rates between 2 and 15 μmol m−2 s−1 were accompanied with an almost twofold increase in growth rates, but photon fluence rates >15 μmol m−2 s−1 did not further enhance growth pointing to low light requirements. From these data optimum, minimum and maximum photon fluence rates and temperatures for growth can be assessed indicating that both diatoms are well acclimated to the fluctuating environmental conditions in the Arctic habitat.  相似文献   

8.
Rhopus antennalis sp. nov. and R. qingdaoensis sp. nov. are described as new to science and R. nigroclavatus (Ashmead, 1902) is first recorded from China. A key to all the known Chinese species of the genus also presented.  相似文献   

9.
Examination of material obtained from the Urdaibai estuary (North Spain) during a 2 year phytoplankton sampling programme revealed a rare species of the genus Chaetoceros, C. salsugineus Takano. The morphology of this small (4·0×5·5?µm) member of the subgenus Hyalochaetae has been described using both light and electron microscopy. Regarding the original material, two new features have been observed: longer chains up to 24 cells and a new type of aperture, bisected by the fusion of central protuberances of adjacent valves. This bloom-forming diatom reached high densities in the poly-euhaline zone of the estuary closely related with high temperatures, denoting its neritic and summer preferences. Maximal cell densities (106–107 cells l?1) were reached in August and September when the water column was completely mixed and the salinity and temperature were about 31 psu and 20°C, respectively. This is the first report of C. salsugineus in Europe and contributes to the knowledge of the morphological and ecological features of this species. Relationships with other small species of the subgenus Hyalochaetae are also discussed.  相似文献   

10.
Tephrosia socotrana sp. nov., a woody species growing on limestone cliffs in north-central Socotra (Yemen), is described and illustrated. strigosa is recorded from Socotra and Yemen for the first time.  相似文献   

11.
Three new Perenniporia species, P. lacerata, P. luteola and P. tianmuensis, are described based on morphological and molecular characters. Perenniporia lacerata is characterized by an annual habit, resupinate and papery basidiocarps with lacerate pores, a dimitic hyphal system with weakly dextrinoid skeletal hyphae, truncate and dextrinoid basidiospores. Perenniporia luteola is distinguished by a perennial habit, resupinate basidiocarps with buff-yellow pore surface, a dimitic hyphal system with dextrinoid skeletal hyphae, non-truncate and dextrinoid basidiospores. Perenniporia tianmuensis differs in its annual habit, pileate basidiocarps, a dimitic hyphal system with strongly dextrinoid skeletal hyphae, non-truncate and dextrinoid basidiospores. Phylogenetic analysis based on ITS and LSU-rDNA regions revealed five clades for 29 species of Perenniporia used in this study. Both morphological and molecular evidence confirmed the placement of three new species in Perenniporia and showed its relationships with similar species in the genus.  相似文献   

12.
《Journal of Asia》2019,22(3):880-888
Arecanut (Areca catechu) is one of the most important commercial crops in India, which grows extensively in the malnad and coastal areas. White grubs are the most important pests on this crop and cause considerable yield loss. Surveys were conducted to record species that are infested with white grubs of Karnataka and Kerala states. Three species of white grubs were collected and described using morphological and molecular characters. A detailed study of male genitalial structures such as aedeagus and endophallus in three species of Leucopholis Dejean, 1833 (Coleoptera: Scarabaeidae: Melolonthinae) viz., Leucopholis lepidophora Blanchard, 1850, Leucopholis burmeisteri Brenske, 1894 and Leucopholis coneophora Burmeister, 1855 showed substantial differences. The mitochondrial cytochrome oxidase subunit I gene was sequenced for molecular identification and phylogenetic analysis in this respect. L. lepidophora, L. burmeisteri and L. coneophora species were successfully identified by employing COXI gene. Phylogenetic analyses revealed that the COXI DNA barcode fragment of Leucopholis species and out-group taxa, available in genetic databases, confirms the species identity.  相似文献   

13.
Wang D  Chen LJ  Duan YX 《动物学研究》2012,33(E3-4):E57-E59
A new record species Heterodera ripae was found in the rhizosphere soil of nettle (Urtica sp.) on the bank of the Mangniu River in Shenyang City, Liaoning Province, China. The new record species can be characterized by vulval cone bifenestrate with circular or subcircular semifenestrae, vulval slit length averaging 34.2 μm, vulval bridge mostly broad, underbridge weak, bullae absent; the second-stage larvae stylet knobs rather wide and slightly projecting anteriorly, tail length averaging 43.7 μm and hyaline region length averaging 22.3 μm.  相似文献   

14.
15.
Diatom taxa in India were first documented by Ehrenberg and subsequently many studies have focused on the Western Ghats and Himalayan mountains while other regional environments were rarely explored. In the current study, the freshwater environs of the saline Lonar Crater Lake were investigated and two new Nitzschia species have been described. Nitzschia kociolekii sp. nov. and Nitzschia tripudio sp. nov. were sampled from bird feeding ponds associated with Lonar Lake. The morphological characters of the new species are similar to N. amphibia and N. frustulum but differ in terms of striae pattern, polymorphic areolae development, fibula and stria density. In addition, larger specimens of N. williamsii, a recently described taxon from Bangalore wetlands of Peninsular India, were found in a waterfalls flowing into Lonar Lake. All three taxa are freshwater diatoms and are possibly endemic to Peninsular India.  相似文献   

16.
Steccherinum cremicolor and S. elongatum are described and illustrated as new species from Taiwan. Steccherinum cremicolor is characterized by strictly resupinate basidiocarps, a fimbriate margin, short spines, generative hyphae dominating in the trama and subiculum, encrusted skeletocystidia, and ellipsoid basidiospores. Steccherinum elongatum has strictly resupinate and membranaceous basidiocarps, bearing fairly long spines, generative hyphae-dominated subiculum, elongated skeletocystidia, and ellipsoid to subglobose basidiospores.  相似文献   

17.
Cell adhesion molecules (CAMs) are important in prokaryotes and eukaryotes for cell–cell and cell–substratum interactions. The characteristics of adhesive proteins in the model diatom Phaeodactylum tricornutum were investigated by bioinformatic analysis and in vivo characterization. Bioinformatic analysis of the protein coding potential of the P. tricornutum genome used an amino‐acid profile that we developed as a new system to identify uncharacterized or novel CAMs. Putative diatom CAMs were identified and seven were characterized in vivo, by generation of transgenic diatom lines overexpressing genes encoding C‐terminal yellow fluorescent protein (YFP) fusion proteins. Three of these selected genes encode proteins with weak similarity to characterized proteins, a c‐type lectin and two fasciclins, whereas the others are novel. The resultant cell lines were investigated for alterations in their adhesive ability. Whole cell‐substratum adhesion strength was measured in a fully turbulent flow chamber, while atomic force microscopy was used to quantify the relative frequency of adhesion, as well as the length and strength of single molecules in the secreted mucilage. Finally, quartz crystal microbalance analysis characterized the visco‐elastic properties and interaction of the mucilage–substratum interface. These combined studies revealed a range of phenotypes affecting adhesion, and led to the identification of candidate proteins involved in diatom adhesion. In summary, our study has for the first time combined bioinformatics and molecular physiological studies to provide new insights into diatom adhesive molecules.  相似文献   

18.
Yorou NS  Agerer R 《Mycologia》2008,100(1):68-80
A common resupinate thelephoroid fungus was collected in northern Guinean seasonal forests in central and north of Benin (West Africa). The species is reminiscent of Tomentella umbrinospora with respect to the color and thickness of basidiomata and rhizomorphs, the shape of basidiospores in frontal view and the size of subicular hyphae. Both species fall phylogenetically within two clades. Based on detailed anatomical comparison (mostly of rhizomorphs and basidiospores) with the holotype of T. umbrinospora and phylogenetic analyses including ITS rDNA sequences of 40 Tomentella species, T. africana is described as a new species. Genetic distance between the newly described species and T. umbrinospora is 12.1-12.9%, based on ITS rDNA sequences. T. africana is characterized anatomically by yellow-brown thick (0.3-0.8 mm) monomitic rhizomorphs that are commonly covered by irregularly shaped thin hyphae, thin- to thick-walled subicular hyphae of two size ranges, clavate and clamped basidia of 30-60 microm and light yellow to pale brown echinulate basidiospores with irregular shape in frontal view. Detailed anatomical and molecular dissimilarities between T. africana and close species are discussed. Differences between irregularly shaped surface thin hyphae and skeletal ones are highlighted. We stress the relevance of rhizomorphal structures in the discrimination of resupinate thelephoroid fungi.  相似文献   

19.
《Mycoscience》2014,55(6):456-461
Two new species, Melanoleuca leucopoda and M. porphyropoda, are described based on collections made from Shenyang City, Liaoning Province, China. Melanoleuca leucopoda is mainly characterized by its whitish stipe with fibrils and oblong spores with elongated warts. Melanoleuca porphyropoda differs from all other Melanoleuca species in lacking cystidia and in having decurrent gills and a purplish stipe. The sequences of internal transcribed spacer regions (ITS1-5.8S-ITS2) of Melanoleuca species were analyzed and the results indicated that two new species clustered into two clades and differed from the other species of the genus. The combination of morphological and molecular data confirmed that the two fungi are new species. The morphological similarity of the new species to other species of Melanoleuca and the systematic position of the two species based on molecular data are also discussed.  相似文献   

20.
Tan KS  Liu LL 《Zoological science》2001,18(9):1275-1289
Thais keluo sp. nov. is described from intertidal shores of southwest Taiwan. The new species is differentiated from five other closely related species, namely T. bitubercularis (Lamarck), T. jubilaea Tan and Sigurdsson, T. clavigera (Küster), T. luteostoma (Holten) and T. rufotincta Tan and Sigurdsson, all of which occur in the South China Sea, on the basis of shell, radula and penis morphology. Thais keluo is also distinguished from the latter three species based on allozyme electrophoresis. The shell of T. keluo is characterized by four raised, spiral bands on the last whorl, one or two small, oblique columellar plica(e) on the inner lip, a finely crenate, thin, narrow, reddish-brown outer lip edge and four white, papillate denticles inside the outer lip of the aperture. In males, the penis is curved with a long, simple flagellum. The UPGMA cluster analysis based on 9 enzyme loci revealed that T. luteostoma is more closely related to T. clavigera than to T. keluo n.sp. The Nei's genetic distance (D) obtained between the new species and T. clavigera/T. luteostoma was 0.31, while T. clavigera and T. luteostoma were separated by a distance of 0.16. Thais rufotincta was separated from the other species by a distance of 0.78. In contrast, phylogenetic analysis of morphological data by maximum parsimony suggested that T. luteostoma was more closely related to T. keluo than to T. clavigera. However, both analyses indicated the close relationship amongst T. clavigera, T. luteostoma and the new species in relation to T. rufotincta.  相似文献   

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