首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Specimens of peripatopsid Onychophora from New Zealand (the viviparous Peripatoid.es novaezealandiae and P. suteri and the oviparous Ooperipatellus insignis) have been analysed by allozyme electrophoresis and compared with three species of viviparous peripatus and 0. insignis from Australia. The data indicate that at least two species of Peripatoides are present, in addition to those described. Populations collected from Dunedin, in the South Island, are not referable on morphological grounds to any described genus. Furthermore, specimens exhibit such a high level of genetic distinctiveness that we speculate they have diverged from the Peripatoides and Euperipatoides lineages prior to the separation of Australia and New Zealand some 95 Myr ago. Specimens referable to 0. insignis from New Zealand are genetically quite distinct from 0. insignis at its type locality in Australia and must be considered endemic.  相似文献   

2.
Six new Ophryotrocha species are described from five whale-falls and two wood-falls off the southern Californian coast. Phylogenetic analyses based on the nuclear gene H3 and the mitochondrial genes COI and 16S using MrBayes and maximum likelihood analyses were performed on 40 dorvilleid taxa and one outgroup. Ophryotrocha batillus sp. nov. is morphologically identical to Ophryotrocha scutellus described from a shallow water whale-fall in the North Atlantic, although the two cryptic species differ genetically. Ophryotrocha langstrumpae sp. nov. is closely related in the molecular phylogenetic analyses to these two sibling species. Ophryotrocha flabella sp. nov. is similar to Ophryotrocha globopalpata, and although there are a few morphological differences, the genetic divergence is low between the two species. Ophryotrocha nauarchus sp. nov. is sexually dimorphic, with males having appendages on the first chaetiger. Ophryotrocha magnadentata sp. nov. and Ophryotrocha longicollaris sp. nov. are sister species in our molecular analyses, and together with O. nauarchus sp. nov. and O. flabella sp. nov. they fall within a clade that includes O. globopalpata and Exallopus jumarsi described from hydrothermal vents in the Pacific Ocean and Ophryotrocha longidentata from the shallow North Atlantic. Our results highlight the remarkable unknown diversity of deep-water habitats and the role of chemosynthetic ecosystems in the evolution of deep-sea life.  相似文献   

3.
4.
Past confusion about leopard frog (genus Rana) species composition in the Tri-State area of the US that includes New York (NY), New Jersey (NJ), and Connecticut (CT) has hindered conservation and management efforts, especially where populations are declining or imperiled. We use nuclear and mitochondrial genetic data to clarify the identification and distribution of leopard frog species in this region. We focus on four problematic frog populations of uncertain species affiliation in northern NJ, southeastern mainland NY, and Staten Island to test the following hypotheses: (1) they are conspecific with Rana sphenocephala or R. pipiens, (2) they are hybrids between R. sphenocephala and R. pipiens, or (3) they represent one or more previously undescribed cryptic taxa. Bayesian phylogenetic and cluster analyses revealed that the four unknown populations collectively form a novel genetic lineage, which represents a previously undescribed cryptic leopard frog species, Rana sp. nov. Statistical support for R. sp. nov. was strong in both the Bayesian (pp=1.0) and maximum-likelihood (bootstrap=99) phylogenetic analyses as well as the Structure cluster analyses. While our data support recognition of R. sp. nov. as a novel species, we recommend further study including fine-scaled sampling and ecological, behavioral, call, and morphological analyses before it is formally described.  相似文献   

5.
North America is a center of biodiversity for freshwater crayfish, with >300 described species, mostly in the family Cambaridae. However, the phylogenetic and phylogeographic relationships among these taxa are poorly understood, despite their ubiquitous occurrence in North American freshwater habitats. Here, we target the geographically widespread Orconectesvirilis and its sister taxa for genetic and morphological investigation. We used sequence data from two mitochondrial genes (16S rRNA and cytochrome oxidase I) and from one nuclear gene (glyceraldehyde-3-phosphate dehydrogenase), as well as morphological data from the male gonopod, to gain insights into phylogenetic relationships among individuals collected in the northeastern United States, where this taxon is considered to be invasive, and from Kansas. Our data reveal evidence for three cryptic species in our collections, in addition to O.virilis sensu stricto; all four clades are separated by both mitochondrial and nuclear sequence data. In addition, two of the newly discovered species, O.sp. nov. A and O.sp. nov. B, are distinguishable from O.virilis by significant differences in gonopod morphology (no data on gonopod morphology were available for O.sp. nov. C). O.sp. nov. A was collected at numerous sites in Massachusetts; additional sampling is required to determine if this species is native to New England. Two other taxa, O.sp. nov. B and O.sp. nov. C, were both collected from sites in eastern Kansas, and historically have probably been considered to be O.nais. In summary, this investigation indicates that this species complex may harbor a great deal of unknown biodiversity over the rest of its described range, and suggests that further attention to the phylogenetics and phylogeography of North American crayfishes may yield interesting insights into the evolution of biodiversity.  相似文献   

6.
Spatial patterns of genetic diversity provide insight into the demography and history of species. Morphologically similar but genetically distinct “cryptic” species are increasingly being recognized in marine organisms through molecular analyses. Such species are, on closer inspection, often discovered to display contrasting life histories or occasionally minor morphological differences; molecular tools can thus be useful indicators of diversity. Bostrychia intricata, a marine red alga, is widely distributed throughout the Southern Hemisphere and comprises many cryptic species. We used mitochondrial cytochrome c oxidase I gene sequences to assess the genetic variation, population genetic structure, and demographic history of B. intricata in New Zealand. Our results supported the existence of three cryptic species of B. intricata (N2, N4, and N5) in New Zealand. Cryptic species N4, which was found throughout New Zealand, showed a higher genetic diversity and wider distribution than the other two species, which were only found in the North Island and northern South Island. Our analyses showed low to moderate genetic differentiation among eastern North Island populations for cryptic species N2, but high differentiation among North and South Island populations for N4, suggesting different population structure between these cryptic species. Data also indicated that N2 has recently undergone population expansion, probably since the Last Glacial Maximum (LGM), while the higher genetic diversity in N4 populations suggests persistence in situ through the LGM. The contrasting population structures and inferred demographic histories of these species highlight that life history can vary greatly even among morphologically indistinguishable taxa.  相似文献   

7.
A previously published DNA barcode survey of red macroalgae in Australia revealed significant cryptic and overlooked diversity for the genus Rhodymenia with recognition of R. novahollandica, R. prolificans, R. stenoglossa, R. wilsonis and an additional four uncharacterized genetic species groups. Since that study, increased sampling effort in Australia has warranted reassessment and reinvestigation of the number of genetic species groups attributed to Rhodymenia and their respective taxonomic affiliations. Using molecular-assisted alpha taxonomy employing the DNA barcode (COI-5P), the present study resolved 188 Australian specimens in 12 genetic species groups assignable to the genus Rhodymenia. Four of these groups were attributed to the previously recognized species (above), whereas some collections from Lord Howe Island were attributed to the New Zealand species R. novazelandica, expanding its biogeographic range. The following seven genetic groups were inconsistent with existing species of Rhodymenia and established as novel taxa: R. compressa sp. nov., R. contortuplicata sp. nov., R. gladiata sp. nov., R. insularis sp. nov., R. lociperonica sp. nov., R. norfolkensis sp. nov. and R. womersleyi sp. nov. Although morphological and biogeographic features were adequate for distinguishing some species of Rhodymenia from Australia, DNA sequencing in combination with morphology and biogeography provided the most reliable means of identification.  相似文献   

8.
A recent survey of the freshwater streams of the Mecula and Yao mountains in the Niassa province of Mozambique resulted in the discovery of a new freshwater crab species. This species is genetically and morphologically distinct from described species from Mozambique or its neighbouring countries, and is described as P otamonautes bellarussus sp. nov. In addition, a new semi‐terrestrial burrowing freshwater crab P otamonautes flavusjo sp. nov. from the Highveld of the Mpumalanga province in South Africa is described based on unique genetic and morphological characters. The phylogenetic affinities of the two new species in relation to the described eastern and southern African Potamonautes species is determined and the biogeographic implications are discussed. © 2014 The Linnean Society of London  相似文献   

9.
Two new species of Phraortes are described from the Ryukyus of Japan. Phraortes kumensis sp. nov. is described from Kume‐jima Island, and P. yonaguniensis sp. nov. from Yonaguni‐jima Island. The morphology of the females, males and eggs of the new species is illustrated.  相似文献   

10.
Microstomum lineare is a common species of fresh and brackish waters found worldwide. Three genes (18S, CO1 and ITS) were sequenced from specimens of M. lineare collected from four countries, and the levels of cryptic diversity and genetic structuring were assessed. Results showed M. lineare has very wide haplotype distributions suggesting higher than expected dispersal capabilities. In addition, three new species were described on the basis of molecular taxonomy: Microstomum artoisi sp. nov., Microstomum tchaikovskyi sp. nov. and Microstomum zicklerorum sp. nov.  相似文献   

11.
Morphological and phylogenetic relationships of the worldwide Mediterranean lichen forming fungus, Parmelina quercina , have been studied. Specimens from western Europe, western North America and southern Australia were analysed using molecular data (nuITS rDNA, nuLSU rDNA and mtSSU rDNA) and selected morphological features (upper cortex maculae, scanning electron microscopy examination of the epicortex, ascospores and conidia shape and size, and amphithecial retrorse rhizines). The results conclusively reveal that: (1) there is not one single species but four separate species in the Mediterranean or sub Mediterranean areas of the world. Parmelina quercina and Parmelina carporrhizans (Euroasiatic species), Parmelina coleae sp. nov. (North America) and Parmelina elixia sp. nov. (Australia); (2) largely debated P. carporrhizans is not a synonym of P. quercina but supported as a valid species circumscribed to Macaronesic relict sites; (3) the geographical isolation of the Australian population is correlated with a large genetic distance; (4) morphological characters (ascospores and conidial variability and thallus epicortex) correlate with the phylogenetic hypothesis; (5) the new or revalidated species within Parmelina quercina are not cryptic species but morphologically recognizable taxa.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 455–467.  相似文献   

12.
Although geologically young, the Hawaiian Islands harbour a rich and remarkably diverse fauna of terrestrial troglobites: more than 70 cave species are known from Kauai, Oahu, Molokai, East Maui, and Hawaii Island. Among the more speciosc groups that have invaded the subterranean biome are the planthoppers (Homoptera Cixiidae) of the genus Oliarus. Five new obligately cavernicolous (troglobitic) Oliarus species which differ in their degree of troglomorphy and male genital structures, are described from lava tubes on the Hawaiian Islands: O. lorettae sp. nov. and O. makaiki sp. nov. from Hawaii Island, O. gagnei sp. nov. and O. ivaikau sp. nov. from Maui Island, and O. kalaupapae sp. nov. from Molokai Island. Short diagnoses of the two troglobitic species already known, 0. polyphemus Fennah, 1973 from Hawaii Island and 0. priola Fennah, 1973 from Maui are provided. Notes on the ecology and distribution of all cavernicolous species are given. Morphological evidence suggests that each of the seven cavernicolous Oliams species from Hawaii represents a separate, independent adaptive shift to underground environments. Potential relationships to the extant epigean species are discussed.  相似文献   

13.
Two new reef coral species, Porites farasani sp. nov. and Porites hadramauti sp. nov. (Scleractinia, Poritidae), are described from the Red Sea and the Gulf of Aden. Porites farasani sp. nov. only occurs in the Farasan Islands in the southern Red Sea, while P. hadramauti sp. nov. has been collected in the Yemen Hadramaut region in the Gulf of Aden. Both species presented striking in situ differences with respect to other Porites species, and were characterized by small encrusting colonies and unusual polyp colouration. In order to test the genetic distinctiveness of P. farasani sp. nov. and P. hadramauti sp. nov. between each other and with respect to other representatives in the genus Porites, we investigated their evolutionary relationships with eight other morphological species of Porites occurring in the Red Sea and in the Gulf of Aden. Two DNA loci, the mitochondrial putative control region and the nuclear ribosomal ITS region, were sequenced, and three species delimitation approaches based on barcoding threshold (Automated Barcoding Gap Discovery) and coalescence theory (Poisson-Tree process, Generalized Mixed Yule Coalescent) were applied. Phylogenetic and species delimitation analyses were overall concordant, resolving P. farasani sp. nov. and P. hadramauti sp. nov. as two divergent but closely related lineages. Of the other morphologically defined Porites species, three were genetically differentiated (P. rus, P. columnaris and P. fontanesii), but five were genetically indistinguishable. The discovery of two regional endemics confirms the importance of the Red Sea and the Gulf of Aden as regions of high biodiversity and suggests the need for an integration of genome-wide molecular data with the re-evaluation of skeletal structures in the systematics of Porites.  相似文献   

14.
The genus Ommatius is firstly reported from Hainan Island. Three species, O. corolla sp. nov., O. huoae sp. nov., O. jianfenglingensis sp. nov., are described as new to science. A key to the species, illustrations of the adults and male genitalia are provided.  相似文献   

15.
16.
The phylogenetic relationships amongst the Arminidae were analysed based upon morphological characters of 58 presently described species or nudibranchs, including 35 previously described Arminidae and 20 new species of Dermatobranchus. From the literature review and anatomical examinations, 43 characters were considered for 78 taxa. These characters were polarized using Berthella canariensis as the outgroup taxon and the type species of several other genera identified from recent publications. The resulting phylogeny supports the monophyly of Arminidae, Dermatobranchus, Doridina, and Proctonotidae. The paraphyly of the Arminina is further demonstrated in this study. Two previously described, but poorly known, species of Indo-Pacific Armina are redescribed, Armina magnaBaba, 1955 and Armina paucifoliataBaba, 1955. The anatomy and taxonomic status of nine previously described species of Dermatobranchus were examined in this study. The anatomy of Dermatobranchus pustulosus (van Hasselt, 1824) has been overlooked since Bergh (1888) illustrated the radula of van Hasselt's specimen. It is redescribed and its range is extended to several new localities in the western Pacific. Dermatobranchus pulcherrimus Miller & Willan, 1986 is considered here as a new synonym of Dermatobranchus rubidus (Gould, 1852). The following 20 species of Dermatobranchus are new and are described in the present paper: Dermatobranchus albineus sp. nov., Dermatobranchus arminus sp. nov., Dermatobranchus caesitius sp. nov., Dermatobranchus caeruleomaculatus sp. nov., Dermatobranchus cymatilis sp. nov., Dermatobranchus dendonephthyphagus sp. nov., Dermatobranchus diagonalis sp. nov., Dermatobranchus earlei sp. nov., Dermatobranchus fasciatus sp. nov., Dermatobranchus funiculus sp. nov., Dermatobranchus kalyptos sp. nov., Dermatobranchus kokonas sp. nov., Dermatobranchus leoni sp. nov., Dermatobranchus microphallus sp. nov., Dermatobranchus oculus sp. nov., Dermatobranchus phyllodes sp. nov., Dermatobranchus piperoides sp. nov., Dermatobranchus rodmani sp. nov., Dermatobranchus semilunus sp. nov., and Dermatobranchus tuberculatus sp. nov. Eighteen of these new taxa are found in the Indo-Pacific tropics and two are found in temperate South Africa, D. albineus and D. arminus. Unique combinations of morphological characters distinguish these as new species of Dermatobranchus. Several species that are externally similar have radically divergent internal morphology, are members of different clades of Dermatobranchus, and represent cryptic species. Especially important is the radular morphology, which shows remarkable diversity of form, probably related directly to the diversification of feeding of members of this clade on various octocorals.  相似文献   

17.
Cryptic diversity represents a major challenge to the accurate assessment of biodiversity, but the combined use of genetic and morphological analyses has proven to be a powerful approach to detect it. This is especially important for groups for which genetic information is not yet available. Here, we studied the highly conspicuous habitat‐forming Pyura stolonifera species complex (Tunicata), which, as has recently been revealed, shows surprising levels of cryptic diversity, but whose systematics and biogeographical patterns in Australasia nonetheless remain poorly understood. We first present detailed taxonomic information of all the species associated with the P. stolonifera species complex. We then proceed to describe the results of an exhaustive survey that included south‐east Australia, Tasmania, and New Zealand. Subsequently, we present morphological and mitonuclear genetic analysis of two unresolved lineages that comprise the species Pyura praeputialis and a species that is formally described here ( Pyura doppelgangera sp. nov. ). Although the ranges of these two species overlap on mainland Australia, we found no sites at which both species live in sympatry, and there was no morphological or genetic evidence of hybridization. Taken together, the present study illustrates the usefulness of a combined morphogenetic approach in unravelling overlooked marine diversity in a relatively well‐studied region. © 2013 The Linnean Society of London  相似文献   

18.
19.
记述海南岛蚋属2新种。琼州纺蚋Simulium(Nev—ermannia) qiongzhouense sp.nov.和天池蚋Simulium(Simulium) tianchi sp.nov.。琼州纺蚋与其近缘种的主要区别是生殖腹板后缘具明显的中突和中骨骨化部末端分叉;天池蚋的主要特征是蛹鳃器基部具坑状器,与其近缘种的主要区别是雌虫足的颜色,雄虫生殖腹板和中骨的形状,蛹腹节7~9背板具栉刺列和幼虫肛鳃每叶分5个副叶。  相似文献   

20.
A revision of chigger mites species being closely related to Neotrombicula talmiensis (Schluger, 1955) has been performed. 2 new species are described: N. pontica sp. n. from Krasnodar Territory (Western Caucasus) and N. sympatrica sp. n. from Krasnodar Territory, Daghestan, Tuva, Armenia, Kirghizia and Turkey (Rize Province). N. pontica sp. n. is closely related to N. carpathica Schluger et Vysotzkaya, 1970 and differs from this species by the larger number of idiosomal setae (NDV = = 75-99 against 63-77), shorter legs (Ip = 782-847 against 844-920, TaIII = 67-74 against 70-80), lesser m-t (0.180 against 0.192), slightly lesser scutum and slightly longer setae. N. sympatrica sp. n. is closely related to N. carpathica and differs from this species by the longer scutal and idiosomal setae (PL = 67-78 against 57-69, H = 65-75 against 57-68, Dmin = 43-52 against 39-48, Dmax = 61-70 against 54-64), longer legs (Ip = 892-973 against 844-920, TaIII = = 77-86 against 70-80) and lesser m-t (0.168 against 0.192). N. carpathica is reported for the first time from Northern Caucasus (Karachai-Cherkess Republic, Kabardino-Balkaria, North Ossetia); N. talmiensis is reported for the first time from Khakasia. Data on joint occurrence of 3 species are reported. The 3 types of sympatric pairs of the species have been found in the Western Caucasus: 1) N. pontica sp. n. and N. sympatrica sp. n., 2) N. sympatrica sp. n., and N. carpathica, 3) N. pontica sp. n., and N. carpathica. Differences between species in that localities, where the joint occurrence was recorded, have been analysed. Sympatric relations between N. sympatrica sp. n. and N. carpathica are characterized by increased value of some general diagnostic characters of these species, such as the length of idiosomal setae and length of legs. Different characters play main distinguishing role in different sympatric localities. Besides that, some local features appear in certain species of sympatric pairs (narrow scutum in 3 samples of N. carpathica, numerous idiosomal setae in 1 sample of N. sympatrica), that differs the populations of the sympatric pair, and also discriminates such aberrant group from other material of the same species. Functions produced by the method of discriminant analysis are proposed for the purpose of diagnostics in talmiensis group. Tests for assumptions of discriminant analysis, such as normality and homogeneity of variances, has been performed beforehand. Verifications of the functions on test samples demonstrated the good quality of its working. Key to species using discriminant functions has been constructed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号