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Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.  相似文献   

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Monoclonal strains of Chaetoceros species were collected from Chinese warm waters. Vegetative cells and resting spores were examined using light microscopy as well as scanning and transmission electron microscopy. Combined morphological and DNA sequence data from the hypervariable D1–D3 region of the nuclear ribosomal large subunit showed the presence of two new species within the section Compressa, herein described as Chaetoceros bifurcatus sp. nov. and C. millipedarius sp. nov. Both species possessed features typical of the section Compressa, but C. bifurcatus was characterized by the heavy intercalary setae fusing and extending together for a distance before diverging. The heavy setae were not visually contorted, lacking poroids and spines, in contrast with how the section Compressa has been defined. Chaetoceros millipedarius was characterized by a horizontal stagger of ordinary intercalary setae when the chain was seen in broad girdle view, making the chain look like a millipede. The two new species were supported by molecular phylogenetic analyses with C. bifurcatus sister to C. contortus var. ornatus, while C. millipedarius was sister to C. contortus var. contortus. Based on the morphological features exhibited in C. bifurcatus, the diagnosis of the section Compressa was emended to exclude “contorted” heavy setae and compressed valve faces.  相似文献   

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The broadly defined genus Chaetophora consisted of species with minute, uniseriate branching filaments enveloped in soft or firm mucilage forming macroscopic growths that are spherical, hemispherical, and tubercular or arbuscular, growing epiphytically on freshwater aquatic plants and other submerged surfaces in standing or fast‐flowing water. Recent molecular analyses clearly showed that this genus was polyphyletic. In this study, eight strains of Chaetophora and three strains of Stigeoclonium were identified and successfully cultured. In combination with the morphological data, a concatenated data set of four markers (18S + 5.8S + ITS2+ partial 28S rDNA) was also used to determine their taxonomic relationships and phylogenetic positions. The molecular analysis resolved the broadly defined Chaetophora to at least two genera. Species with a globose thallus of genus Chaetophora formed a separate monophyletic clade, which clearly separated from, a type of lobe‐form Chaetophora species. Therefore, we propose to erect a new genus, Chaetophoropsis, which includes all globose species of the Chaetophora. Chaetophoropsis aershanensis was determined to be a new species, based on its special characteristic of profuse long rhizoids. Stigeoclonium polyrhizum, as the closest relative to Chaetophoropsis, revealed its distant relationships to other species of Stigeoclonium. A globose thallus with a thick, soft mucilage matrix, and special rhizoidal branches lent further support to the placement of S. polyrhizum in the genus Chaetophoropsis and had the closest relationship to C. aershanensis. Taxonomic diversity was proven by distinctive morphological differences and by phylogenetic divergence in the broadly defined Chaetophora identified herein.  相似文献   

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The diatom genus Chaetoceros is one of the most abundant and diverse phytoplankton in marine and brackish waters worldwide. Within this genus, Chaetoceros socialis has been cited as one of the most common species. However, recent studies from different geographic areas have shown the presence of pseudo‐cryptic diversity within the C. socialis complex. Members of this complex are characterized by curved chains (primary colonies) aggregating into globular clusters, where one of the four setae of each cell curves toward the center of the cluster and the other three orient outwards. New light and electron microscopy observations as well as molecular data on marine planktonic diatoms from the coastal waters off Chile revealed the presence of two new species, Chaetoceros sporotruncatus sp. nov. and C. dichatoensis. sp. nov. belonging to the C. socialis complex. The two new species are similar to other members of the complex (i.e., C. socialis and C. gelidus) in the primary and secondary structure of the colony, the orientation pattern of the setae, and the valve ultrastructure. The only morphological characters that can be used to differentiate the species of this complex are aspects related to resting spore morphology. The two newly described species are closely related to each other and form a sister clade to C. gelidus in molecular phylogenies. We also provide a phylogenetic status along with the morphological characterization of C. radicans and C. cintus, which are genetically related to the C. socialis complex.  相似文献   

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Gerres microphthalmus sp. nov., described on the basis of the holotype and 38 paratypes, has a limited distribution in Japan, including Tanega Island, southeastern Kyushu, southern Shikoku, and southern Kii Peninsula, central Honshu. It has not been recorded from the Ryukyu Islands. The species is the fourth member of the “G. filamentosus complex,” characterized by an elongated second dorsal fin spine, the others being G. filamentosus, G. infasciatus, and G. macracanthus. Gerres microphthalmus sp. nov. is most similar to G. filamentosus in overall body appearance, but differs from the latter in having smaller eyes (8%–11% of standard length vs. 10%–16% in the latter), a higher orbit diameter ratio (as % of snout length) (93%–143% of snout vs. 71%–104% of snout), and fewer pored lateral line scales (40–43 vs. 43–46). The limited distribution pattern of the new species is discussed with G. equulus and Lates japonicus (Centropomidae) having a limited distribution similar to that of the new species. Received: June 28, 2001 / Revised: November 13, 2001 / Accepted: December 10, 2001  相似文献   

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Forest or mouse shrews (Myosorex) represent a small but important radiation of African shrews generally adapted to montane and/or temperate conditions. The status of populations from Zimbabwe, Mozambique, and the north of South Africa has long been unclear because of the variability of traits that have traditionally been ‘diagnostic’ for the currently recognized South African taxa. We report molecular (mitochondrial DNA and nuclear DNA), craniometric, and morphological data from newly collected series of Myosorex from Zimbabwe (East Highlands), Mozambique (Mount Gorogonsa, Gorongosa National Park), and the Limpopo Province of South Africa (Soutpansberg Range) in the context of the available museum collections from southern and eastern Africa and published DNA sequences. Molecular data demonstrate close genetic similarity between populations from Mozambique and Zimbabwe, and this well‐supported clade (herein described as a new species, M yosorex meesteri sp. nov. ) is the sister group of all South African taxa, except for Myosorex longicaudatus Meester & Dippenaar, 1978. Populations of Myosorex in Limpopo Province (herein tentatively assigned to Myosorex cf. tenuis) are cladistically distinct from both Myosorex varius (Smuts, 1832) and Myosorex cafer (Sundevall, 1846), and diverged from M. varius at approximately the same time (2.7 Mya) as M. cafer and Myosorex sclateri Thomas & Schwann, 1905 diverged (2.4 Mya). Morphometric data are mostly discordant with the molecular data. For example, clearly distinct molecular clades overlap considerably in craniometric variables. On the other hand, extreme size differentiation occurs between genetically closely related populations in the Soutpansberg Range, which coincides with the bissection of the mountain range by the dry Sand River Valley, indicating the potential for strong intraspecific phenotypic divergence in these shrews. © 2013 The Linnean Society of London  相似文献   

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The Middle East is at the southeastern borderline of the range of the subterranean amphipod Niphargus. The review of new and published data identified two new species and set the guidelines for the future research in the area. The genus in this part of the world seems to be insufficiently studied. The taxonomic status of Niphargus valachicus, population identified as N. spoeckeri and some populations, identified as N. nadarini, need to be reviewed. According to present data, we expect the highest diversity in Western Turkey. The eventual new records of the genus in the Middle East can be expected from those areas where even the longest periods of drought in the recent geological history did not affect the water supply.  相似文献   

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A molecular survey of red algae collected by technical divers and submersibles from 90 m in the mesophotic zone off the coast of Bermuda revealed three species assignable to the Kallymeniaceae. Two of the species are representative of recently described genera centered in the western Pacific in Australia and New Zealand, Austrokallymenia and Psaromenia and the third from the Mediterranean Sea and the eastern Atlantic, Nothokallymenia. A phylogenetic analysis of concatenated mitochondrial (COI‐5P) and chloroplast (rbcL) genes, as well as morphological characteristics, revealed that two are shown to be new species with distant closest relatives (N. erosa and Psaromenia septentrionalis), while the third represents a deep water western Atlantic species now moved to an Australasian genus (A. westii).  相似文献   

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 A new liparid, Careproctus parvidiscus, is described on the basis of a single specimen (177 mm in standard length) collected from the southern Okhotsk Sea, off Shiretoko Point, Hokkaido, Japan, at 400–700 m depth. It is distinguished from other congeners by the following combination of the characters: 50 dorsal fin rays, 44 anal fin rays, 10 + 47 = 57 vertebrae, 2 pleural ribs, 14 pyloric caeca being slender and pointed, 2 suprabranchial pores, narrower gill opening, longer lower lobe of pectoral fin, base of uppermost pectoral fin ray almost on a level with center of eye, rudimentary disk, dusky peritoneum, and black stomach. Received: June 13, 2001 / Revised: December 7, 2001 / Accepted: December 22, 2001  相似文献   

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Vanzosaura rubricauda (Boulenger, 1902) is a small‐bodied gymnophthalmid lizard widespread in dry biomes of South America. Throughout its distribution, V. rubricauda populations experience contrasting environmental conditions, and a marked disjunction occurs in the central portion of the Cerrado biome. Previous studies indicate that V. rubricauda may be a species complex, and here we used mitochondrial DNA data and external morphology to test for population differentiation and its systematic implications for the genus. We found three geographically cohesive groups recovered as well resolved, and strongly supported mitochondrial DNA (mtDNA) haploclades that are differentiated with respect to morphometry, meristics, and colour pattern. In light of the observed differences, we propose a new taxonomic rearrangement of the genus, where we: (1) restrict V. rubricauda to Chaco and western Cerrado regions; (2) resurrect V anzosaura multiscutata (Amaral, 1933) comb. nov. for Caatinga populations; and (3) describe V anzosaura savanicola sp. nov. for the eastern Cerrado region of Brazil. The new species is diagnosed from its congeners by having longer limbs and tail, fewer smooth subcaudals, and genetic distances ranging from 5 to 13%. The new species, along with other recent discoveries, highlights the Jalapão‐Serra Geral region as one of the most important areas of endemism for Cerrado squamates. © 2014 The Linnean Society of London  相似文献   

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This paper describes a new genus and species of shrew from the Pleistocene (levels 4, 5, and 6) of the Gran Dolina site, located in the Sierra de Atapuerca (Burgos, Spain). Dolinasorex glyphodon gen. et sp. nov. (Mammalia, Soricidae) is a type of large‐sized soricine, endemic in character, which inhabited the Sierra de Atapuerca in the last part of the Early Pleistocene (c. 780–900 kya). Morphometric and phylogenetic analyses indicate that the new species is more closely related to Asiatic forms than to the species Beremendia fissidens with its primarily European distribution. The main palaeoecological and palaeobiogeographical implications of the new taxon in the area around Atapuerca and in the Iberian Peninsula in general are discussed. The paper also presents a tentative phylogeny for the Soricinae subfamily in Eurasia, including for the first time exclusively fossil species, producing results that may prove to be of great interest for more complete studies in the future. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 904–925.  相似文献   

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