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1.
Frank B. Crandall 《Hydrobiologia》1993,266(1-3):175-184
The genus Akrostomum was erected by Grube in 1840 for a single species A. stannii which remained a nomen dubium until redescribed by Bürger in 1895 as Amphiporus stanniusi. Bürger (1909) described Drepanophorus valdiviae which shared many characters with A. stannii. Stiasny-Wijnhoff (1923) noted that these two forms belonged neither to Amphiporus nor Drepanophorus and united them in a new genus Valdivianemertes but did not mention the earlier name Akrostomum nor a family affiliation. Several major characters are examined. The nomenclatural status is analyzed, with retention of the junior synonym Valdivianemertes, and the type species is fixed as V. stannii by subsequent designation. Family affiliation is discussed, and the genus is transferred to the Cratenemertidae.  相似文献   

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Trebouxiophytes of the genus Prasiola are well known in Antarctica, where they are among the most important primary producers. Although many aspects of their biology have been thoroughly investigated, the scarcity of molecular data has so far prevented an accurate assessment of their taxonomy and phylogenetic position. Using sequences of the chloroplast genes rbcL and psaB, we demonstrate the existence of three cryptic species that were previously confused under Prasiola crispa (Lightfoot) Kützing. Genuine P. crispa occurs in Antarctica; its presence was confirmed by comparison with the rbcL sequence of the type specimen (from the Isle of Skye, Scotland). Prasiola antarctica Kützing is resurrected as an independent species to designate algae with gross morphology identical to P. crispa but robustly placed in a separate lineage. The third species is represented by specimens identified as P. calophylla (Carmichael ex Greville) Kützing in previous studies, but clearly separated from European P. calophylla (type locality: Argyll, Scotland); this alga is described as P. glacialis sp. nov. The molecular data demonstrated the presence of P. crispa in Maritime and Continental Antarctica. P. antarctica was recorded from the Antarctic Peninsula and Shetland Islands, and P. glacialis from the Southern Ocean islands and coast. Such unexpected cryptic diversity highlights the need for a taxonomic reassessment of many published Antarctic records of P. crispa. The results also indicate that marine species of Prasiola form a well‐supported monophyletic group, whereas the phylogenetic diversity of freshwater species is higher than previously suspected (at least three separate lineages within the genus include species living in this type of environments).  相似文献   

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Results from critical studies of the original collections upon which Spongites Kützing, 1841 is based have led to the designation of S. fruticulosa as lectotype species and to the resurrection and recognition of Spongites as a distinct genus of Corallinaceae (Rhodophyta). Spongites is characterized by the absence of geniculae, uniporate tetrasporangial conceptacles, a multistratose non-palisade and non-coaxial medulla (“hypothallium”) and cortex (“perithallium”), fusions between cells of adjacent filaments, and trichocytes which are solitary or arranged in a vertical series. Since at least 1883, the Kützing epithet “fruticulosa” has been misapplied widely to a taxon with multiporate tetrasporangial conceptacles, whereas the type collection of S. fruticulosa possesses uniporate tetrasporangial conceptacles. Of the six original species, three (S. fruticulosa, S. racemosa, S. stalactitica) are retained in Spongites; S. dentata is referred to Lithophyllum and S. nodosa to Lithothamnion as distinct species; and S. confluens is regarded to be conspecific with Lithophyllum incrustans Philippi. Detailed morphogological-anatomical accounts of specimens in the type collections are presented along with relevant historical data on the genus and on the various species studied. The relationships of Spongites to Neogoniolithon and to other genera of Corallinaceae also are discussed.  相似文献   

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Four species of the genus Evergestis Hübner, 1816–1826 are recognized from NE China, of which E. pallidata (Hufnagel 1767) is reported for the first time from China. The adults and genitalia of the species are briefly redescribed and illustrated with their distributional ranges, host plants and biology. A key to species of the genus based on the external characters is provided.  相似文献   

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Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493–1506, 2010; Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.  相似文献   

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Thirteen species of the genus Parapoynx Hübner (1825) are recognised from China, including P. qujingalis, a new species described herein. A key to the Chinese species is provided. The adults of the new species and the genital structures of all examined species are illustrated.  相似文献   

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Abstract

Trichostomum schlimii Müll.Hal., a neglected Colombian taxon, is transferred to the genus Pseudosymblepharis Broth. as Pseudosymblepharis schlimii (Müll.Hal.) comb. nov. The species, known only from the type locality in Santa Marta, Colombia, is newly reported for the moss floras of Bolivia, Brazil, Dominican Republic, Ecuador, Guiana, Peru, and Venezuela. It is described, lectotypified, illustrated, and mapped. Diagnostic characters, and distinction from one closely related American species within the genus are discussed. Trichostomum mollissimum (Broth. ex E.B.Bartram) H.A.Crum and Pseudosymblepharis guatemalensis (E.B.Bartram) B.H.Allen are reduced to the synonymy of Pseudosymblepharis schlimii.  相似文献   

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The taxonomic relationship between Gelidium elegans Kützing and Gelidium subfastigiatum Okamura, two morphologically similar species of the red algal genus Gelidium (Gelidiaceae) growing in the north‐western Pacific, was critically re‐examined. Gelidium subfastigiatum has been distinguished from G. elegans by its more robust thalli, which have antrorse tooth‐like branches, although their distinction has been said to be often difficult or impossible. We determined the nuclear encoded internal transcribed spacer 1 (ITS1) for 14 samples from eight populations of this G. elegans/ G. subfastigiatum complex, and two types of ITS1 sequences were found. Analysis of seasonal variations of subterminal portions of major branches revealed that this complex includes two groups: one possessing the type 1 ITS1 sequence and antrorse tooth‐like branches that are subterminally thickened and widened during only colder months, and another possessing the type 2 ITS1 sequence and thin and narrow branches throughout the year. These groups should be recognized as separate species; the former is assigned to G. subfastigiatum and the latter to G. elegans.  相似文献   

12.
A new lacazelline brachiopod species is described from reef caves in the outer reef slope zone off Addu and South Male atolls in the Maldive Islands, Indian Ocean. Based on anatomical features of the soft parts, shell morphology and shell microstructure the new taxon is assigned to the genus Ospreyella Lüter and Wörheide 2003 in the subfamily Lacazellinae of the family Thecideidae. This new species, here named O. maldiviana and representing the first occurrence of the genus in the Indian Ocean, is compared with the type species O. depressa Luter from Osprey Reef, Coral Sea, Australia. Comparisons are made between Ospreyella (now two species) and the other extant lacazelline genera Lacazella Munier‐Chalmas (three species) and Pajaudina Logan (one species).  相似文献   

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Species of the heterotrophic green microalgal genus Prototheca and related taxa were phylogenetically analyzed based on the nuclear small subunit (SSU) and the 5′ end of the large subunit (LSU) rRNA gene (rDNA) sequences. We propose restricting the genus Prototheca to the four species: P. moriformis Krüger, P. stagnora (Cooke) Pore, P. ulmea Pore, and P. zopfii Krüger. The main diagnostic feature of these taxa is the absence of growth on trehalose.Of these, it was suggested that P. moriformis should be merged into P. zopfii; P. moriformis and three varieties of P. zopfii constituted a paraphyletic assemblage with estimated short evolutionary distances. The trehalose‐assimilating strains (Prototheca wickerhamii Tubaki et Soneda strains and Auxenochlorella protothecoides (Krüger) Kalina et Pun?ochá?ová SAG 211‐7a), together with an invertebrate pathogen Helicosporidium sp., diverged before the radiation of the four species of Prototheca in the SSU rDNA and composite (SSU rDNA plus LSU rDNA) analyses. Comparison between the results from physiological data in this work (fermentative pattern) and those described earlier (growth requirements) lead us to propose a hypothesis that the phenotypic variation, which did not represent diagnostic characters for species delimitation, may reflect the history of genetic diversification within the genus Prototheca as inferred from rDNA sequence characters.  相似文献   

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The first phylogenetic analysis of the genus Thyridosmylus Krüger is presented. All species from China were scored in a morphological analysis, along with extralimital species from India (Thyridosmylus pustulatus Kimmins) and Madagascar (Thyridosmylus marmoratus Fraser), and were compared with out‐group exemplars from Spilosmylus Kolbe, Thaumatosmylus Krüger and Osmylus Latreille. A monophyletic Thyridosmylus sister to Spilosmylus is confirmed based on this analysis, with the Malagasy Thyridosmylus marmoratus as sister to the Oriental Thyridosmylus species. Based on the results of this analysis, the biogeography of world Thyridosmylus is discussed. It is proposed that the genus originated in Gondwana no later than the Late Cretaceous (88 Ma) before the break‐up of the Madagascar–India continent. A new species, Thyridosmylus paralangii sp.n., is described from Guangxi Province, whereas two species [Thyridosmylus langii (McLachlan) and Thyridosmylus perspicillaris minor Kimmins] are recorded from China for the first time. Four synonyms are identified: Thyridosmylus laetus Yang et al. syn.n. , Thyridosmylus similaminor Yang syn.n. , Thyridosmylus vulgatus Yang syn.n. and Thyridosmylus mimoroides Yang syn.n. A key to the species of the world is provided.  相似文献   

17.
The new genus, Acryptolechia (Lepidoptera, Cryptolechiidae), with the type species Cryptolechia malacobyrsa Meyrick, 1921 is described. The differences between this species and the type species of the genus Cryptolechia, Zeller 1852 (C. straminella Zeller, 1852) are shown. The genus Meleonoma Meyrick, 1914 is the closest to the new one. In addition to the type species, the new genus includes Acryptolechia facunda (Meyrick, 1910) comb. n. from India and A. torophanes (Meyrick, 1935) comb. n. from China.  相似文献   

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We redescribe Cyrtostrombidium longisomum Lynn & Gilron, 1993, the type species of the genus Cyrtostrombidium, and describe the new species Cyrtostrombidium paralongisomum n. sp. using live observation, protargol staining and molecular data. The morphological characters of these two species are clearly distinct, i.e., dikinetid numbers in the girdle and ventral kineties; however, it is difficult to separate them by 18S rDNA sequences because they differ by only 8 bp, indicating that 18S rDNA sequences are insufficient for separating different species in the genus Cyrtostrombidium. We not only observed the position of the oral primordium in the genus Cyrtostrombidium but also observed a possibly homoplasious trait, a dorsal split in the girdle kinety, in (1) Apostrombidium, (2) Varistrombidium, and (3) Cyrtostrombidium/Williophrya. This partially supports the hypothesis of somatic ciliary pattern evolution recently put forth by Agatha and Strüder‐Kypke.  相似文献   

20.
New data about the Pselaphinae fauna of South-Western Bulgaria (Belasitsa Mts) are presented. Bythinus angustioculus sp. n. is described. The genus Protamaurops Müller, 1944 and the species Plectophloeus nubigena (Reitter, 1877) and Bryaxis leonhardi Reitter, 1902 are reported for the first time in Bulgaria.  相似文献   

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