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1.
In this article we describe a new Paramacrobiotus species of the areolatus group by means of integrative taxonomy. Together with the detailed morphological and morphometric data (obtained from light and scanning electron microscopy) we also provide DNA sequences of four universal molecular markers used in tardigrade taxonomy (three nDNA fragments: 18S rRNA, 28S rRNA, ITS-2, and one mtDNA fragment: COI). The animals of Paramacrobiotus lachowskae sp. nov. are similar to several species of the areolatus complex and the eggshell ornamentation is similar to that of two species of the richtersi group. Therefore, the new species can be easily distinguished from the areolatus group species by egg morphology (dome-like, wrinkled processes with long flexible spines/filaments covered by fine short hairs) and from species of the richtersi complex by the absence of the microplacoid. Paramacrobiotus lachowskae sp. nov. is the 43rd species reported from Colombia and fifth Paramacrobiotus species from this South American country.

http://zoobank.org/urn:lsid:zoobank.org:pub:FEDC11D3-DCCF-4699-A704-CE6DEA1CDED4  相似文献   


2.
The cosmopolitanism paradigm in the biogeography of freshwater invertebrates is currently being replaced by non-cosmopolitanism or continental endemism. Benthic water fleas (Cladocera) from the family Chydoridae were the first group of freshwater invertebrates for which non-cosmopolitanism and cryptic diversity was substantiated by morphological studies. Yet, little is known about genetic differentiation and evolutionary history of chydorid species complexes. Here we present the first analysis of the genetic versus morphological differentiation in a benthic cladoceran species complex—Chydorus sphaericus s. str. using sequence variation in a nuclear (ribosomal internal transcribed spacer 2, ITS-2) and a mitochondrial (cytochrome c oxidase subunit I, COI) genes in 50 Holarctic localities. We tested for continental endemism and cryptic diversity predicted by previous morphological studies. We found evidence for the presence of at least seven putative regional species in the Holarctic, at least three of them being distributed beyond a single continent. While the molecular and sexual stage characters showed general concordance on species lineages, parthenogenetic female characters lacked resolution or were unassociated with molecular lineages. We conclude that cryptic regional lineages of benthic cladocerans are apparent and that the sexual stages represent the most informative morphological source of species characters for this environmental indicator group.  相似文献   

3.
The O. avara group of Oecetis is formally defined to include 4 described species, O. avara (Banks), O. disjuncta (Banks), O. elata Denning & Sykora, and O. metlacenis Bueno-Soria, and 15 new species. Oecetis marquesi Bueno-Soria, previously considered a member of the O. avara group, is treated as incertae sedis to species group, but is also redescribed and treated in the current work. New species described here (with their respective distributions) include: O. acciptrina (Costa Rica, Panama, Ecuador), O. agosta (Mexico), O. angularis (Guatemala to Ecuador), O. apache (SW USA), O. campana (Ecuador), O. constricta (Mexico to Ecuador, Venezuela, and Trinidad), O. houghtoni (North America), O. maritza (Costa Rica), O. mexicana (Mexico to Ecuador), O. patula (Guatemala, Nicaragua), O. protrusa (Mexico to Ecuador), O. sordida (Mexico, USA, Canada), O. tumida (Costa Rica), O. uncata (Costa Rica), and O. verrucula (Mexico to Costa Rica). A key to the species is also provided.  相似文献   

4.
The tropical alga previously recognized as Gibsmithia hawaiiensis (Dumontiaceae, Rhodophyta) was recently suggested to represent a complex of species distributed throughout the Indo‐Pacific Ocean and characterized by a peculiar combination of hairy (pilose) gelatinous lobes growing on cartilaginous stalks. Phylogenetic reconstructions based on three genetic markers are presented here with the inclusion of new samples. Further diversity is reported within the complex, with nine lineages spread in four major phylogenetic groups. The threshold between intra‐ and interspecific relationships was assessed by species delimitation methods, which indicate the existence of 8–10 putative species in the complex. Two species belonging to the G. hawaiiensis complex are described here: Gibsmithia malayensis sp. nov. from the Coral Triangle and Gibsmithia indopacifica sp. nov., widely distributed in the Central and Eastern Indo‐Pacific. Morphological differences in the vegetative and reproductive structures of the newly described species are provided and compared to the previously described species of the complex. Additional lineages represent putative species, which await further investigation to clarify their taxonomic status. Gibsmithia hawaiiensis sensu stricto is confirmed to be endemic to the Hawaiian Islands, and Gibsmithia eilatensis is apparently confined to the Red Sea, with an expanded distribution in the region. New records of the G. hawaiiensis complex are reported from Egypt, Saudi Arabia, Indonesia, Philippines, and the Federated States of Micronesia, indicating that the complex is more broadly distributed than previously considered. The isolated position of Gibsmithia within the Dumontiaceae is corroborated by molecular data.  相似文献   

5.
Nematode diversity may seriously be underestimated when taking into account cryptic speciation. Thoracostoma trachygaster is commonly found in kelp holdfasts along the California coastline and was recently shown to consist of at least two distinct molecular clades (I and II). Here, we provide detailed morphological analysis of both clades, based on measurements taken from video vouchers of respectively eight and 16 individuals from the previous study, as well as 80 newly collected specimens from four Californian beaches. The latter were vouchered, measured, and then subjected to molecular analyses of the mitochondrial cytochrome oxidase c subunit I (COI) gene, and the ribosomal D2D3 and internal transcribed spacer (ITS) regions. This integrative approach shows that the three molecular clades are phylogenetically and morphologically distinct species, but a combination of morphological characters is needed to distinguish them. Two new species, Thoracostoma fatimae sp. nov. and Thoracostoma igniferum sp. nov. , are identified and described. The spicule length of T. fatimae sp. nov. is significantly shorter than that of T. trachygaster. Thoracostoma igniferum sp. nov. can be distinguished by the irregular posterior edge of the cephalic capsule and the two internal subdorsal tropis‐like projections in the wall of the cephalic capsule, which are lacking in T. fatimae sp. nov. and T. trachygaster. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 18–35.  相似文献   

6.
Six new species of the Drosophila robusta species group are described from Southeast Asian Islands. Kalimantan and Sunda Islands lie east of Bali, from which Drosophila barobusta sp.nov and D. uncinata sp.nov belong to the lacertosa subgroup, and D. sungaicola sp.nov, D. baliensis sp.nov, D. hitam sp.nov and D. subaquatica sp.nov to the okadai subgroup. The robusta group from Southeast Asian tropics exclusively inhabits streamsides in mountainous highlands with an elevation of more than 600 m from the sea level.  相似文献   

7.
Faunistic survey using a DNA taxonomy approach may provide different results from morphological methods, especially for small and understudied animals. In this study, we report the results from morphometric analyses (linear measurements of the lorica) and DNA taxonomy (generalized mixed Yule coalescent model on the barcoding mtDNA locus cytochrome c oxidase subunit I) performed on 15 clonal lineages of the rotifer Brachionus plicatilis species complex from six Iranian inland saltwaters. The DNA taxonomy approach found more units of diversity (four) than the morphometric approach (two) in the studied rotifers. Three of the taxa identified in this study are already known as described valid species or as‐yet unnamed lineages, but a new, additional lineage is also identified from Iran. © 2014 The Linnean Society of London  相似文献   

8.
Drosophila (Sophophora) subpulchrella Takamori and Watabe, sp. nov., of the D. suzukii subgroup in the D. melanogaster species group, is described from Japan and southern China, and compared with its sibling species, D. pulchrella Tan et al. distributed in the Yun‐Gui Highland, south‐western China. The results of cross‐experiments show a complete pre‐mating isolation between D. subpulchrella and D. pulchrella.  相似文献   

9.
Eupeyerimhoffia archimedis (Strasser, 1965) is redescribed based on several specimens collected at a number of sites close to the type locality on Sicily, Italy. Scanning electron microscopy is used to illustrate several unusual morphological characters for a member of the Glomerida for the first time. A fragment of the mitochondrial COI gene (668bp) is sequenced for the first time in Eupeyerimhoffia to provide a species-specific barcode and to gain first insights into the genetic distances between the genera in the widespread family Protoglomeridae. The novel sequences are compared to representatives of all other genera of the family: Protoglomeris vasconica (Brölemann, 1897) from northern Spain, the dwarfed Glomerellina laurae Silvestri, 1908 from Italy and Glomeroides primus (Silvestri, 1929) from western North America. The addition of COI sequences from the two other families of the Glomerida renders the family Protoglomeridae paraphyletic with Glomeroides primus being more closely related to Glomeridella minima (Latzel, 1884) than to the other genera in the family. The large genetic distances (13.2–16.8%) between Eupeyerimhoffia and the other genera in the order, as well as its unusual morphological characters, including unique morphological adaptations to roll into a ball, are probably an indication of the old age of the group.  相似文献   

10.
Correct taxonomy is a prerequisite for biological research, but currently it is undergoing a serious crisis, resulting in the neglect of many highly diverse groups of organisms. In nematodes, species delimitation remains problematic due to their high morphological plasticity. Evolutionary approaches using DNA sequences can potentially overcome the problems caused by morphology, but they are also affected by theoretical flaws. A holistic approach with a combination of morphological and molecular methods can therefore produce a straightforward delimitation of species. The present study investigates the taxonomic status of some highly divergent mitochondrial haplotypes in the Rhabditis ( Pellioditis ) marina species complex by using a combination of molecular and morphological tools. We used three molecular markers (COI, ITS, D2D3) and performed phylogenetic analyses. Subsequently, morphometric data from nearly all lineages were analysed with multivariate techniques. We included R. ( P. ) mediterranea and R. (R.) nidrosiensis to infer species status of the observed lineages. The results showed that highly divergent genotypic clusters were accompanied by morphological differences, and we created a graphical polytomous key for future identifications. This study indisputably demonstrates that R. ( P. ) marina and R. ( P. ) mediterranea belong to a huge species complex and that biodiversity in free-living marine nematodes may be seriously underestimated.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 1–15.  相似文献   

11.
12.
Understanding the factors promoting species formation is a major task in evolutionary research. Here, we employ an integrative approach to study the evolutionary history of the Californian scrub white oak species complex (genus Quercus). To infer the relative importance of geographical isolation and ecological divergence in driving the speciation process, we (i) analysed inter‐ and intraspecific patterns of genetic differentiation and employed an approximate Bayesian computation (ABC) framework to evaluate different plausible scenarios of species divergence. In a second step, we (ii) linked the inferred divergence pathways with current and past species distribution models (SDMs) and (iii) tested for niche differentiation and phylogenetic niche conservatism across taxa. ABC analyses showed that the most plausible scenario is the one considering the divergence of two main lineages followed by a more recent pulse of speciation. Genotypic data in conjunction with SDMs and niche differentiation analyses support that different factors (geography vs. environment) and modes of speciation (parapatry, allopatry and maybe sympatry) have played a role in the divergence process within this complex. We found no significant relationship between genetic differentiation and niche overlap, which probably reflects niche lability and/or that multiple factors, have contributed to speciation. Our study shows that different mechanisms can drive divergence even among closely related taxa representing early stages of species formation and exemplifies the importance of adopting integrative approaches to get a better understanding of the speciation process.  相似文献   

13.
Populations of the marine benthic red macroalgae Hypnea musciformis and Hypnea pseudomusciformis along the Atlantic and Pacific Oceans were tested for phylogeographic structure using the DNA barcode COI‐5P combined with rbcL for the construction of the phylogenetic tree. Strong patterns of genetic structure were detected across 210 COI‐5P DNA sequences, and 37 COI‐5P haplotypes were found, using multiple statistical approaches. Hypnea musciformis was found in the Northeast and Northwest Atlantic, the Mediterrean Sea, Namibia, and along the Pacific coast of Mexico. Two new putative species were detected, Hypnea sp. 1 in the Caribbean Sea and Hypnea sp. 2 in the Dominican Republic. Three distinct marine phylogeographic provinces were recognized in the Southern Hemisphere for H. pseudomusciformis: Uruguay, South‐Southeast Brazil, and Northeast Brazil. The degree of genetic isolation and distinctness among these provinces varied considerably. The Uruguay province was the most genetically distinct, as characterized by four unique haplotypes not shared with any of the Brazilian populations. Statistically significant results support both, isolation by distance and isolation by environment hypotheses, explaining the formation and mantainance of phylogeographic structuring along the Uruguay‐Brazil coast. Geographic, taxonomic and molecular marker concordances were found between our H. pseudomusciformis results and published studies. Furthermore, our data indicate that the Hawaiian introduced populations of H. musciformis contain Hypnea sp. 1 haplotypes, the current known distribution of which is restricted to the Caribbean.  相似文献   

14.
Two new species of Leptobotia are here described as L. rotundilobus from the Xin'an-Jiang of the upper Qiantang-Jiang basin in both Anhui and Zhejiang Provinces and the Cao'e-Jiang in Zhejiang Province, and L. paucipinna from the Qing-Jiang of the middle Chang-Jiang basin in Hubei Province, South China. Both have a plain brown body as found in L. bellacauda Bohlen & Šlechtová, 2016, L. microphthalma Fu & Ye, 1983, L. posterodorsalis Chen & Lan, 1992 and L. tientainensis (Wu, 1930). The two new species are distinct from these species in vertebral counts, further from L. posterodorsalis in vent placement and further from the other three species in pectoral-fin length. Both differ in caudal-fin coloration and shape, and dorsal-fin location and coloration, and also in internal morphology. Their validity is confirmed by their own monophyly recovered in a phylogenetic analysis based on the mitochondrial cyt b and COI genes.  相似文献   

15.
In this study, species complex of Turkish Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) populations was determined by PCR‐based DNA analysis. According to phylogenetic analyses, the B. tabaci samples have been identified within three generic groups. A major part of the samples belonged to two invasive species, either Middle East–Asia Minor 1 (MEAM1) or Mediterranean (MED). In addition to these two invasive species, several samples collected from greenhouses and cotton fields have been found to be related to Middle East–Asia Minor 2 (MEAM2), which is the first record of Turkish B. tabaci species complex.  相似文献   

16.
The genus Eudonia is rarely recorded in Tibet despite having a wide occurrence in the plateau. In the taxonomy of the genus, the morphological characters are insufficient to delimit the closely related congeners due to the subtly interspecific differences and conspicuously intraspecific variability. In this study, the Tibetan species are studied with an integrative approach using molecular data and morphological characters. It is found that the number of Eudonia species in Tibet accounts for about 20% of the total species previously catalogued for the genus in China. Five species are described as new to science: Eudonia galonglaensis Li, sp. nov., E. varians Li, sp. nov., E. triangulata Li, sp. nov., E. angusta Li, sp. nov., and E. bomiensis Li, sp. nov. The potential distribution of Chinese Eudonia is predicted and illustrated using MaxEnt and DIVA-GIS. The results reveal the exceptionally high species diversity of Eudonia in Tibet for the first time, demonstrate that the integrative morphological and molecular approach is highly effective for resolving the difficult-to-distinguish morphologies, and predict the region of China to the south of 35°N and to the east of 95°E as having potentially high Eudonia species diversity.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:EA3C5D21-9674-46E4-838D-48D5A098314B  相似文献   


17.
Fourteen polymorphic microsatellites were isolated from Neogobius kessleri, a benthic fish of Ponto‐Caspian origin which has been recently introduced into the Middle and Upper Danube River. Number of alleles and heterozygosity per locus in a sample of 32 fish individuals ranged from two to four and from 0.13 to 0.75, respectively. These primers will be useful in determining the population structure of N. kessleri. In addition, successful cross‐amplification was obtained for four related species, N. melanostomus, N. fluviatilis, N. gymnotrachelus and Proterorhinus marmoratus. These microsatellite loci may be useful for the evaluation of the origin of non‐native goby populations.  相似文献   

18.
This revision deals with the Zygothrica samoaensis species group, which includes 15 species, five of which are described as new to science. Two synonymies are proposed: Z. vietnamensis Grimaldi, 1990, as a junior synonym of Z. flavofinira Takada, 1976, and Z. britannia Grimaldi, 1990, as a junior synonym of Z. malaysiana Grimaldi, 1990. The samoaensis group is divided into three species subgroups: (i) the samoaensis subgroup, consisting of nine species, including a new species, Z. australiaensis sp. nov.; (ii) the fijiana subgroup of Z. fijiana Takada, 1976, and two new species, Z. triscutellaris sp. nov. and Z. bicornigera sp. nov.; and (iii) the leptorostra subgroup of Z. leptorostra Grimaldi, 1990, and two new species, Z. pimacula sp. nov. and Z. quintamaculata sp. nov. Supplementary information on geographic distribution is provided for some species, as well as a key to all species of the samoaensis group. Zygothrica kokodana Grimaldi, 1990, and Z. paleovitta Grimaldi, 1990, have closer affinity with the hirticornis and the quadrivittata species groups, respectively, and so are moved to the corresponding genus Hirtodrosophila.  相似文献   

19.
Integrative taxonomy is a recently developed approach that uses multiple lines of evidence such as molecular, morphological, ecological and geographical data to test species limits, and it stands as one of the most promising approaches to species delimitation in taxonomically difficult groups. The Pnigalio soemius complex (Hymenoptera: Eulophidae) represents an interesting taxonomical and ecological study case, as it is characterized by a lack of informative morphological characters, deep mitochondrial divergence, and is susceptible to infection by parthenogenesis‐inducing Rickettsia. We tested the effectiveness of an integrative taxonomy approach in delimiting species within the P. soemius complex. We analysed two molecular markers (COI and ITS2) using different methods, performed multivariate analysis on morphometric data and exploited ecological data such as host–plant system associations, geographical separation, and the prevalence, type and effects of endosymbiont infection. The challenge of resolving different levels of resolution in the data was met by setting up a formal procedure of data integration within and between conflicting independent lines of evidence. An iterative corroboration process of multiple sources of data eventually indicated the existence of several cryptic species that can be treated as stable taxonomic hypotheses. Furthermore, the integrative approach confirmed a trend towards host specificity within the presumed polyphagous P. soemius and suggested that Rickettsia could have played a major role in the reproductive isolation and genetic diversification of at least two species.  相似文献   

20.
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