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The Holothuriidae is one of the three established families within the large holothuroid order Aspidochirotida. The approximately 185 recognized species of this family are commonly classified in five nominal genera: Actinopyga , Bohadschia , Holothuria , Pearsonothuria and Labidodemas. Maximum parsimony analyses on morphological characters, as inferred from type and nontype material of the five genera, revealed that Labidodemas comprises highly derived species that arose from within the genus Holothuria . The paraphyletic status of the latter, large (148 assumed valid species) and morphologically diverse genus has recently been recognized and is here confirmed and discussed. Nevertheless, we adopt a Darwinian or eclectic classification for Labidodemas , which we retain at generic level within the Holothuriidae. We compare our phylogeny of the Holothuriidae with previous classifications of its genera and subgenera, and make suggestions concerning possible systematic changes.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 103−120.  相似文献   

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A new species of Delamarella Chappuis, 1954 (Copepoda, Harpacticoida, Latiremidae), D. obscura sp. nov. , is described from sandy beaches along the western Black Sea coast of Turkey, using both light and scanning electron microscopy. Additional morphological observations of the closely related D. galateae Cottarelli, 1971 are presented, based on topotype material from Sardinia and newly collected specimens from mainland Italy. Previous records of D. karamani Petkovski, 1957 from the Bulgarian Black Sea coast are based on misidentifications and should be attributed to D. obscura sp. nov. All three species are morphologically similar, and criteria based on meristic and ornamentation characters are provided to distinguish them. Examination of copepodid V ♂ intermoult stages provided new insights into the morphology of the highly transformed P4 exopod of the adult male and its homology with reference to the female. A reassessment of the generic distinctiveness of Delamarella and the monotypic genus Latiremus Božić, 1969 revealed that morphological criteria, traditionally employed to separate both genera, are all essentially unsound and based on erroneous reports in the literature. Consequently, Latiremus is relegated to a junior synonym of the type genus, leaving Delamarella and Arbutifera Huys & Kunz, 1988 as the only remaining valid genera in the family.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 263–281.  相似文献   

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Khaosokia caricoides , D.A. Simpson, Chayam. & J. Parn., a newly discovered genus and species of Cyperaceae is described and illustrated. The genus is characterized by a narrowly paniculate dioecious inflorescence with 2–4 nodes, each of the nodes having a leaf-like inflorescence bract that exceeds the inflorescence. Spikelets in both sexes are linear-cylindric and each flower has seven perianth bristles. The nutlet was immature in the specimens examined. The photosynthetic pathway is C3. Khaosokia is endemic to limestone cliffs in peninsular Thailand; its conservation status is assessed as Vulnerable (VU B1a + 2a). It has affinities to tribes Cariceae, Dulichieae and some members of Scirpeae, but the exact nature of these relationships has yet to be determined. A revised key to the genera of Cyperaceae in Thailand is presented.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 357–364.  相似文献   

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The genus Labulla Simon is circumscribed in phylogenetic terms to include the species Labulla thoracica (Wider), L. flahaulti Simon and L. machadoi sp. nov. The genital anatomy of the genus is described in detail and the taxonomy of the genus is reviewed. The monophyly of Labulla is supported by numerous morphological apomorphies of the male palp and female epigynum. Based on a cladistic analysis, a new genus, Pecado gen. nov. , is erected to place Labulla impudica Denis, from Northern Africa. Lepthyphantes insularis Saito and ' Labulla ' nepula Tikader, both formerly included in Labulla , are not congeneric with the type species of Labulla .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 359–404.  相似文献   

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Recent molecular phylogenetic studies of the terrestrial snail genus Albinaria have caused a radical reassessment of its taxonomy. These studies, however, were limited to western species. This paper examines mitochondrial 12S sequences and nuclear ITS1 & 2 sequences of both eastern and western species, and demonstrates that Albinaria, in its most recent definition, is not monophyletic. Both molecular datasets place ' Albinaria ' hedenborgi from Lebanon in a well-supported clade with species of the genus Cristataria , distributed south-east of the vicariant range of Albinaria . The remaining species from Cyprus, Turkey and Greece constitute a well-supported monophyletic group. These two clades form geographical clusters, whereas Albinaria in the current definition (including ' A. '  hedenborgi ) has a disjunct distribution. ' A.' hedenborgi should therefore be classified with Cristataria , together with the morphologically similar and geographically close ' A. '  nadimi .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 531−542.  相似文献   

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Representatives of the genus Praomys occur throughout the African intertropical zone. It is unclear how many species this genus contains, nor do we know the exact distribution ranges and phylogenetic relationships of these taxa. Using molecular (16S rRNA gene sequencing) and morphological (multivariate craniometry) analyses we clarify the taxonomy and phylogenetic relationships among the Praomys occurring in Africa's lowland tropical rainforests. We studied most species known from this area, based on specimens collected in seven countries (Guinea, Ivory Coast, Cameroon, Central African Republic, Gabon, Congo Republic and Democratic Republic of Congo). In our study, Praomys appears to be monophyletic. Our results identify two species complexes: the jacksoni complex includes at least two species ( P. jacksoni and P. mutoni ) and the tullbergi complex contains at least four species ( P. tullbergi , P. rostratus , P. misonnei , P. petteri ). Although the 16S rRNA gene appears insufficient to resolve the phylogenetic relationships among all the members of the tullbergi species complex, it is suitable for the identification of most of the studied species, and its use has allowed us to redefine the geographical limits of several species.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 539–553.  相似文献   

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This review of the genus Dichopteris De Zigno is based on the original fossil specimens collected from the Lower Jurassic of the Grey Limestones of Veneto (Northern Italy). The cuticular diagnosis of the genus is emended and only Dichopteris visianica De Zigno is retained within the genus. In addition, transverse and longitudinal sections of cuticles examined using a transmission electron microscope (TEM) indicate close similarities between D. visianica and other pteridosperm cuticles, especially the occurrence of granules arranged in areas of different densities in the epidermal cells and stomatal apparatus. Moreover, the dichotomy and the impressive size of the frond of D. visianica imply a specific architecture with a typical arrangement of the pinnae and pinnules. They preclude an herbaceous habit for the plant. Finally, architectural, microstructural and ultrastructural observations are consistent with palaeoclimatic and palaeoenvironmental data, and most probably support an understorey habit for D. visianica .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 313–332.  相似文献   

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The taxonomy of rain forest species of the genus Chlorophytum in central and west Africa has to date been difficult to resolve. Plants collected in the Guineo-Congolean plant geographical region deposited in several herbaria formed the basis for a morphometric analysis using Principal Component Analyses and including 16 characters. In total, 166 individuals were included from 461 herbarium collections, from which 57 seeds were scanned to investigate the surface structures. Eight species are recognized, including one with three subspecies and another with three varieties. Four new combinations are proposed ( Chlorophytum comosum (Thunb.) Jacques var. bipindense (Engl. & K. Krause) A.D. Poulsen & Nordal, C. comosum (Thunb.) Jacques var. sparsiflorum (Baker) A.D. Poulsen & Nordal, C. lancifolium Baker ssp. cordatum (Engl.) A.D. Poulsen & Nordal, and C. lancifolium Baker ssp. togoense (Engl.) A.D. Poulsen & Nordal), ten new synonyms are introduced and three lectotypes are designated.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 1–20.  相似文献   

14.
A new species of Viola (Violaceae) from north-western Yunnan, China, is described and illustrated. Viola dimorphophylla Y. S. Chen & Q. E. Yang sp. nov. is endemic to Zhongdian County, north-western Yunnan, and is very easily distinguishable from all other Chinese species of the genus by having obviously dimorphic leaves, with the basal ones being long petiolate, undivided and widely cordate, and the cauline ones sessile, linear and verticillate.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 115–119.  相似文献   

15.
The eresid spider genus Eresus is morphologically and ecologically conservative. At least three species occur in Europe. However, deep genetic divergence among geographical samples within two species, E. cinnaberinus and E. sandaliatus , may suggest more cryptic species. In the present study we investigate the genetic cohesion of the third species, Eresus walckenaeri , throughout its eastern Mediterranean distribution range, relative to the E. cinnaberinus–E. sandaliatus species complex. Eresus walckenaeri specimens were monophyletic. Genetic discreteness of E. walckenaeri in a region of sympatry with its sister species in Greece provides evidence for species integrity of E. walckenaeri within the European Eresus species complex. Eresus walckenaeri exhibited high concordance between geographical location and mtDNA genealogy. Two major phylogeographical clades were found in the Greek–Turkish and Syrian–Israel parts of the investigated area, respectively (∼6.5% sequence divergence). Concordance between geography and genetic divergence was further observed between Aegean island samples and their corresponding Greek and Turkish mainland samples, suggesting regional subdivision with gradual but potentially high dispersal propensity. Monophyly and limited regional distribution indicate Mediterranean endemic origin.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 86 , 1–9.  相似文献   

16.
Koelreuteria Laxm., a genus in the tribe Koelreuterieae (Sapindaceae), includes three tree species that are widely recognized as having horticultural merit. The two more closely related species, K. bipinnata Franch. and K. elegans (Seem.) A. C. Sm., are easily distinguished from K. paniculata Laxm. by their bipinnate leaves. In this study, both species were investigated cytogenetically and their karyotypes and heterochromatic patterns were compared. Koelreuteria bipinnata and K. elegans ssp. formosana (Hayata) F. G. Mey. both have 2 n  = 32 but their karyotypes present slight morphological differences when observed using conventional staining. Chromosome banding patterns are reported for the first time for this genus. Both species exhibit terminal heterochromatic blocks, as revealed by C-Giemsa and C-CMA3, but the band size varies between the species. Koelreuteria bipinnata has larger heterochromatic blocks and more GC-rich segments, while in K. elegans ssp. formosana these bands are smaller. The relationship between the karyotype features in these closely related species is discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 451–455.  相似文献   

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Chromosome variation in the genus Pinellia (Araceae) in China and Japan   总被引:3,自引:0,他引:3  
The chromosome numbers of 23 populations belonging to seven species of Pinellia Tenore were counted. The basic chromosome number of all the species studied was x  = 13, and the previously reported basic numbers x  = 9 and x  = 14 in P. ternata and P. cordata were not confirmed. Chromosome numbers of 2 n  = 26 in P. polyphylla and 2 n  = 78 in P. integrifolia are reported for the first time. Heptaploid (7 x ) and nonuploid (9 x ) are new ploidy levels reported for P. ternata , and hexaploid for P. cordata. Taxonomic, phylogenetic and phytogeographical inferences are made for the genus. Particular attention was given to P. ternata , the most widely distributed species in the genus, and considerable variation of chromosome number was found in its different populations. Based on chromosome studies of 11 populations of P. ternata , together with 12 populations reported in previous studies, the lower reaches of the Yangze River are identified as its centre of origin. From there it dispersed, with generation of hexaploid, heptaploid, octoploid and nonuploid forms.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 449–455.  相似文献   

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A new species of the thermophylic Tethyan relict prawn Typhlatya is described from two anchialine caves near Perpignan (southern France). The new species is closely related to a congener known only from a freshwater cave at Castellón (eastern Spain), about 400 km to the south-west, differing apparently only in the size and shape of the rostrum and the armature of the dactylus of the fifth pereiopod. Based on palaeogeographical evidence and assuming a sister-group relationship between both species, we suggest that their common ancestor could not be older than early Pliocene in age, and that it was already a stygobiont taxon adapted to live in shallow-water marine crevicular habitats. This ancestor would have vanished from the western Mediterranean after the cooling associated with the onset of northern Hemisphere glaciation, about 3 Mya, as documented for other Mediterranean marine taxa. Indeed, the genus is completely stygobiont and does not occur in fluvial environments. The Pyrenees represent a watershed boundary that eliminates the possibility of the derivation of one species from the other by active dispersal after establishment in continental waters.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 387–414.  相似文献   

19.
The phylogenetic relationships of 27 north-eastern Atlantic and Mediterranean blennioids are analysed based on a total of 1001 bp from a combined fragment of the 12S and 16S mitochondrial rDNA. The most relevant results with implications in current blenniid taxonomy are: (1) Lipophrys pholis and Lipophrys (=  Paralipophrys ) trigloides are included in a well-supported clade that by the rule of precedence must be named Lipophrys ; (2) the sister species of this clade are not the remaining species of the genus Lipophrys but instead a monotypic genus comprising Coryphoblennius galerita ; (3) the smaller species of Lipophrys were recovered in another well-supported and independent clade, which we propose to be recognized as Microlipophrys ; (4) although some authors included the genera Salaria and Lipophrys in a single group we have never recovered such a relationship. Instead, Salaria is more closely related to the genera Scartella and Parablennius ; (5) the genus Parablennius , which was never recovered as a monophyletic clade, is very diverse and may include several distinct lineages; (6) the relative position of Aidablennius sphynx casts some doubts on the currently recognized relationships between the different blenniid tribes. Meristic, morphological, behavioural and ecological characters support our results and are also discussed. The possible roles of the tropical West African coast and the Mediterranean in the diversification of blenniids are discussed.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 86 , 283–295.  相似文献   

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Tragopogon cazorlanum (Asteraceae: Lactuceae) is proposed as a new Spanish species with distribution restricted to the Baetic mountains (south-eastern Spain). Its morphological, palynological, chromosomal, biogeographical and ecological features are discussed, as well as its main relationships and differences with reference to other Spanish species of the genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 505–511.  相似文献   

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