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Numerous reptile species have been divided into subspecies. Although this classification may capture the morphological variation within species, it often conceals significant species diversity because many subspecies actually represent species under lineage‐based species concepts. The lizard Holcosus undulatus is a common, widely distributed, monotypic species in Middle America. However, 12 subspecies of this taxon were recognized until the early 1970s. We used two lineage‐based methods for species delimitation to re‐evaluate species limits within H. undulatus with DNA sequence and morphological data. We included all the previously recognized subspecies of H. undulatus except H. u. miadis. Holcosus undulatus was exclusive. In addition, H. u. amphigrammus, H. u. gaigeae, H. u. hartwegi, H. u. parvus, H. u. pulcher, H. u. sinister, H. u. stuarti, H. u. thomasi and H. u. undulatus were supported as distinct evolutionary lineages based on the molecular and morphological evidence. We therefore elevate all of these subspecies to species rank. In addition, two separate mitochondrial lineages may represent cryptic, undescribed species within H. undulatus. The morphological distinctness and allopatry of H. u. miadis and H. u. pulcher, as well as the high genetic divergence of the latter species, suggest that they also represent distinct evolutionary species. Our results also suggest that additional species diversity may still be hidden within the H. u. amphigrammus, H. u. parvus, H. u. sinister and H. u. undulatus lineages. This work supports resurrection of overlooked diversity within Holcosus, which has important implications for the conservation of this genus in Middle America. © 2015 The Linnean Society of London  相似文献   

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The cicada Pauropsalta annulata Goding & Froggatt, 1904 comprises several distinct song types across its known distribution in eastern Australia, with these songs being statistically distinguishable from one another. Here we use spatial analysis of adult morphology and plant species associations to test further the hypothesis that P. annulata song types represent a complex of cryptic species. To structure this investigation we contrast different approaches and expectations given under the framework of ecological speciation with those of the recognition concept of species. Plotting the geographical distributions of these cicadas revealed that each of the P. annulata song types have independent geographical distributions, with relatively small areas of overlap. ‘Predicted distribution’ modelling revealed that the distribution of each song type forms a unique climatic envelope, which suggests that abiotic factors (rather than interactions among the cicadas themselves) influence the geographical representation of the different song types. One song type has consistent differences in male genitalia, and female ovipositor length differs significantly among three of the other song types. Each song type is strongly associated with a small number of tree species, and these associations are maintained in areas of sympatry. The spatial comparisons made in this study suggest that the P. annulata song types investigated actually represent three species. One of these species is represented by two of the song types originally recognized, and these appear to intergrade in sympatry, and thus represent subspecies. The spatial consistency of the plant associations and morphology exhibited by these (sub)species is significant because it represents an ecological measure of species stability. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 553–565.  相似文献   

5.
The rodent genus Praomys is widely distributed in the African tropics. The species are cryptic, rendering the species taxonomy unclear. There are differences of opinion concerning the specific status of Praomys misonnei and Praomys tullbergi, and their geographical distribution. We sequenced the cytochrome b and/or the 16S gene of 221 specimens from 12 countries in order to evaluate the genetic variability within these two species, and to precisely determine their geographical distribution. Morphological and morphometrical analyses on the sequenced specimens were also performed to find criteria useful for the identification of museum specimens. Our results confirm that P. misonnei and P. tullbergi are two valid species that can be separated by molecular data. However, no single discrete morphological character or simple metric measurement can be used to discriminate them. The percentage of misclassified individuals in multivariate discriminant analysis is relatively high (10%). The two species have allopatric distributions: P. tullbergi occurs in West Africa, from eastern Guinea to western Ghana, and P. misonnei is widely distributed from eastern Ghana to western Kenya. Within P. misonnei we identified three or four major geographical clades: a West Central African clade, an East African clade, a Nigerian clade, and a possible West African clade. Within P. misonnei, high geographical morphometrical variability was also identified. The role of both rivers and Pleistocene forest refugia in promoting speciation within the genus Praomys is discussed. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 397–419.  相似文献   

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ABSTRACT

The planorbid species that were described by Shuichi (Syuiti) Mori from Japan have long been enigmatic and their taxonomy has been highly confused. This situation is also an impediment to action for the conservation of Japanese planorbids which are one of the most threatened freshwater snail groups in the country. Based on our examination of Shuichi Mori’s collection stored in the Kyoto University Museum, type materials of the taxa described by him are re-illustrated and re-examined for the first time. Our examination suggested that Gyraulus amplificatus (Mori, 1938) is not a morphological form of Gyraulus biwaensis but a distinct species. Gyraulus pulcher (Mori, 1938) can be regarded as a junior synonym of Gyraulus chinensis.  相似文献   

7.
Species with specialized ecological interactions present significant conservation challenges. In plants that attract pollinators with pollinator‐specific chemical signals, geographical variation in pollinator species may indicate the presence of cryptic plant taxa. We investigated this phenomenon in the rare sexually deceptive orchid Drakaea elastica using a molecular phylogenetic analysis to resolve pollinator species boundaries, pollinator choice experiments and a population genetic study of the orchid. Pollinator choice experiments demonstrated the existence of two ecotypes within D. elastica, each attracting their own related but phylogenetically distinct pollinator species. Despite the presence of ecotypes, population genetic differentiation was low across populations at six microsatellite loci (FST = 0.026). However, Bayesian STRUCTURE analysis revealed two genetic clusters, broadly congruent with the ecotype distributions. These ecotypes may represent adaptation to regional variation in pollinator availability and perhaps the early stages of speciation, with pronounced morphological and genetic differences yet to evolve. Resolution of the taxonomic status of the D. elastica ecotypes is required as this has implications for conservation efforts and allocation of management funding. Furthermore, any reintroduction programmes must incorporate knowledge of ecotype distribution and pollinator availability to ensure reproductive success in restored populations. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 124–140.  相似文献   

8.
The species of Necremnus attacking two invasive pests of tomato and canola in Europe and North America, respectively, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), have been revised using an integrative taxonomy approach. Molecular data from the mitochondrial cytochrome oxidase c subunit I and the nuclear D2 expansion region of the 28S ribosomal subunit and internal transcribed spacer 2, the discovery of new morphological features, and study of type material resulted in the delineation of three species groups, the Necremnus artynes, Necremnus cosconius, and Necremnus tidius groups, the discovery of four new species, and the resurrection of three taxa from synonymy. Lectotypes have been designated for 13 species originally described in Eulophus by Walker. Although Necremnus has not been revised, an illustrated key is given to differentiate 23 recognized European species. The key, type images, and treatments of the three species groups will enable more accurate identification of the valid species of Necremnus in the future. They will also benefit biological control practitioners of pest species. The ecological consequences of the new taxonomic concepts are discussed. © 2015 The Authors. Zoological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London  相似文献   

9.
The worm‐like snakes (Scolecophidia; approximately 400 nominal extant species) have a conservative morphology and are among the most poorly‐known terrestrial vertebrates. Although molecular evidence has helped determine their higher‐level relationships, such data have rarely been used to discriminate among species. We generated a molecular data set for the continental Australian blindsnakes (genus Ramphotyphlops) to determine the concordance of molecular and morphological information in the taxonomic recognition of species. Our dataset included 741 specimens morphologically attributed to 27 nominal Ramphotyphlops species. We proposed species hypotheses (SHs) after analysis of sequences from a variable mitochondrial gene (cytochrome b) and examined these SHs with additional evidence from a nuclear gene (prolactin receptor) and geographical data. Although the nuclear marker was not as fast‐evolving and discriminating as the mitochondrial marker, there was congruence among the mitochondrial, nuclear, and geographical data, suggesting that the actual number of species is at least two times the current number of recognized, nominal species. Several biogeographical barriers and complex phytogeographical and geological patterns appeared to be involved in the division of some burrowing snake populations and, by consequence, in their diversification and speciation through isolation. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 427–441.  相似文献   

10.
The Mexican pseudothelphusid crabs are classified in one subfamily, three tribes, and 13 genera. Up to now, 56 species have been recognized, distributed in a strictly Neotropical pattern, with some of them reaching the state of Sonora on the western slope of Mexico. The tribe Pseudothelphusini is the most diverse, with five genera and 35 species, all of them endemic to Mexico: the two most species‐rich genera are Pseudothelphusa, with 23 species, and Tehuana, with eight species; Epithelphusa includes two species, whereas Disparithelphusa and Smalleyus are monotypic. The Pseudothelphusini lack an updated systematic revision, which could serve as a framework to analyse the monophyletic origin of the group, to clarify the relationships among genera and species, as well as to resolve the taxonomic status of various species complexes. In the present study, an exhaustive morphological revision was conducted using somatic and sexual characters. A phylogenetic analysis was performed using 77 characters and 183 character states, taken from 41 species. Ten trees of the same length were obtained using PAUP 4.0 through a heuristic search. The results show that the tribe as it is actually known constitutes a paraphyletic group, in which the species of Epithelphusa and Pseudothelphusa puntarenas are excluded from the internal group. According to the obtained results, the tribe Pseudothelphusini s.s. includes five genera: Smalleyus, Pseudothelphusa, Tehuana, and two new ones to accommodate Pseudothelphusa galloi and Pseudothelphusa sulcifrons, respectively. This new arrangement considers the provisional suppression of the genus Disparithelphusa, which remained as another species of Pseudothelphusa throughout the cladistic analysis. The phylogenetic results show a strong congruence with the distribution of the species, in several cases grouping species that form morphological clines along a geographical gradient. The previously proposed southern origin of the tribe Pseudothelphusini gains support with the results obtained. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 457–481  相似文献   

11.
Habitat fragmentation is a major force that will influence the evolution of a species and its distribution range. Pomatoschistus minutus, the sand goby, has a North Atlantic–Mediterranean distribution and shows various level of habitat fragmentation along its geographic repartition. The use of mitochondrial sequences of the cytochrome b (cyt b) gene and two co‐dominant sets of nuclear markers (introns and microsatellites) allowed us to describe the relationships between P. minutus populations belonging to several different geographical regions of Europe and to assess the structure of populations inhabiting the Golfe du Lion, along the French Mediterranean coast. The present study confirms that the taxon located in the Adriatic Sea (Venice) should be considered as a distinct species, separated approximately 1.75 Mya. The comparison of P. minutus between the Atlantic and western Mediterranean coasts using polymorphic co‐dominant markers revealed that they belong to two demographically independent units, and thus could be considered as well as distinct species, more recently separated (0.3 Mya). The Pleistocene glaciations seem therefore to have played an important role in the diversification of this complex. Finally, at a regional scale in the Golfe du Lion, P. minutus appears to form a single huge homogeneous population. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 175–198.  相似文献   

12.
Revision of the Neotropical fern genus Danaea (Marattiaceae) has resulted in the recognition of ten new species, which are here for the first time presented to the scientific audience. Morphological and molecular data suggest that the genus consists of three monophyletic subgenera that are circumscribed here. A key is provided to aid species identification. The geographical ranges of the species are summarized and discussed with regard to speciation. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 360–385.  相似文献   

13.
Given sufficient time and limited gene flow, evolutionary lineages tend to transform into separate species. Mechanisms preventing assimilation during repeated gene‐flow events include divergent adaptations and the development of pre‐ or postzygotic isolation. We analysed the morphological and genetic boundaries of three species of the rock lizard clade Darevskiarudis’ (Darevskia rudis, Darevskia valentini, and Darevskia portschinskii) in relation to the environment, and tried to reconstruct evolutionary pathways underlying the observed separation among the species. We studied the geographic distribution of the scalation traits, microsatellite genotypes, and mitochondrial haplotypes. Our analyses showed consistent morphological and genetic patterns at the centre of the ranges for each species, but asymmetric distribution of alleles and scalation characters within the current contact zones among the species. The genetic and morphological diversification of the clade has been shaped during glacial isolation in an area of Southern Caucasus, away from the Black Sea Coast. The ancestral lineage of D. portschinskii separated from the common D. rudis–D. valentini lineage in the middle Pleistocene, and the two latter lineages separated in relatively recent geological time. Neither of the lineages attained complete lineage sorting; moreover, isolation and migration modelling have helped to detect recombinant gene flow from D. rudis to D. portschinskii (but not to D. valentini). This is most likely linked with climatically more similar suitable habitats between D. rudis and D. portschinskii than between D. valentini and the other two species. In itself, the isolation period was insufficient for the development of intrinsic isolation mechanisms in the system studied. Thus, differential landscape‐dependent selection within the contact zones is likely to have triggered the rapid development of isolation mechanisms. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 876–892.  相似文献   

14.
Doryopteris adornata is described as a new species from west‐central South America (Brazil, Bolivia, Paraguay, and Argentina). The dense indument of scales on the abaxial surface of the lamina is the most prominent diagnostic feature of this new species. Illustrations of the diagnostic characters are provided, as well as a table comparing the morphological characters of D. adornata with those of the two most similar species. The ecology and distribution are described. The conservation status for the new species using World Conservation Union (IUCN) guidelines/criteria is recommended. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 73–77.  相似文献   

15.
The taxonomy of the amphi‐Atlantic tree genus Carapa (Meliaceae) has long been controversial. Of the three species currently recognized in the genus, two are known to present substantial morphological variation that has been used in the past to distinguish several taxa, most of which are currently placed in synonymy. Here, a combination of field observations, univariate analyses of leaf, floral and seed characters and principal coordinate analyses of floral characters in the context of a molecular phylogenetic analysis was used to investigate the patterns of variation and delimit morphological species anew in the genus. These results support the recognition of 27 species in Carapa, of which 16 are previously described and 11 are new. In general, phylogenetically related species occurred in the same geographical area, but were morphologically distinct. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 186–221.  相似文献   

16.
Erysimum includes 150–350 species distributed in the Northern Hemisphere, with Eurasia being the centre of greatest diversity. It is well known for its taxonomic complexity as a result of overlapping morphological characters. We present the first densely sampled phylogenetic analysis of Erysimum using internal transcribed spacer (ITS) DNA sequences from c. 85% of the species (117 for the first time), representing the full range of morphological variation and geographical distribution. We used several approaches to reconstruct phylogenetic relationships, dating of diversification and patterns of evolution of morphological characters in the genus. Ancestral‐state reconstructions of four morphological diagnostic characters were performed using maximum parsimony, maximum likelihood and Bayesian methods. Our phylogenetic framework strongly supports the monophyly of Erysimum and recovers some well‐supported clades that are geographically, rather than morphologically, correlated. Our study confirms the placement of Erysimum in lineage I and reveals two Malcolmia spp. (M. maritima and M. orsiniana) as its sister taxa. The results suggest that the biennial duration and caespitose habit (vs. annual or perennial duration and herbaceous or woody habit) and large, yellow, glabrous (vs. small, non‐yellow, pubescent) petals are ancestral in Erysimum. The ancestral‐state reconstruction results show that annual vs. perennial and woody vs. herbaceous features have been independently derived several times. The dating analyses suggest an early radiation of Erysimum during the late Pliocene or early Pleistocene. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 497–522.  相似文献   

17.
Endemic atyids of southern Europe have been ascribed to Dugastella, and to subterranean Typhlatya and Troglocaris: Dugastella is epigean, and Typhlatya and Troglocaris are subterranean. An extensive collection from all centres of distribution in southern Europe (excepting the Caucasus) was morphologically examined. A taxonomic redefinition of the group, at different levels, is based on recently published and newly generated molecular phylogeny, whereas newly established taxa have also been morphologically defined. The accordance between the phylogenetic tree and the geographical distributions suggested that a re‐evaluation of some traditionally used morphological characters should generate the most parsimonious solution: this enabled a novel taxonomic division. Gallocaris gen. nov. is erected for the French Troglocaris inermis Fage, 1937, which is more closely related to the epigean Dugastella valentina (Ferrer Galdiano, 1924) than to its supposed congeners. Both western Mediterranean Typhlatya species are closely related to their Caribbean congeners. All other European cave shrimps constitute a monophylum, Troglocaris, which is divisible into subgenera (already with available names): the holo‐Dinaric Troglocaris (Troglocaris) Dormitzer, 1853, south‐eastern mero‐Dinaric Troglocaris (Troglocaridella) Babi?, 1922, and Troglocaris (Spelaeocaris) Matja?i?, 1956, and the Caucasian Troglocaris (Xiphocaridinella) Sadovsky, 1930. Four new species are described: Troglocaris (Troglocaris) bosnica sp. nov. , Troglocaris (Spelaeocaris) prasence sp. nov. , Troglocaris (Spelaeocaris) kapelana sp. nov. , and Troglocaris (Spelaeocaris) neglecta sp. nov. The distribution of all established species is shown, and the value of the morphological characters is discussed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 786–818.  相似文献   

18.
To gain an overview of the variation in the Dactylorhiza incarnata/maculata complex in northern Poland, ten plastid DNA regions (seven microsatellite and three indel loci) and 23 morphometric characters were used. In total, 972 and 480 samples from 64 and 31 populations were utilized for the genetic and morphometric analyses, respectively. One hundred and forty‐one haplotypes that have not been reported previously were recognized. The continuity of morphological characters between the studied species and the impact of post‐glacial colonization on the observed complexity in the Dactylorhiza incarnata/maculata complex were concluded. It was confirmed that the allotetraploid group of D. majalis s.s. has inherited its plastid genome from D. maculata s.l., specifically from D. maculata ssp. fuchsii. In addition, some of the haplotypes found in D. majalis s.s. were distinct and evidently not present in the preserved D. maculata s.l. Although possible gene flow and introgression between two subspecies of the D. maculata s.l. group were indicated, we suggest that they should be treated as separate evolutionary units. Both the common and rare haplotypes show a similar pattern of geographical distribution for all four taxa analysed, which suggests that hybridization took place relatively recently, shortly after the retreat of the ice sheet. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 121–137.  相似文献   

19.
The abundant Sundaland forest frog, Rana chalconota, has long been considered a single widespread species, although some authors have recommended its division into regional subspecies. The discovery of co‐occurring pairs of morphologically distinct populations in three widely separated parts of the range led to a morphological and molecular analysis of populations from all parts of the known range. The results suggest that R. chalconota consists of at least seven species from Thailand through Borneo and Java. Existing names are applied to three of these species, R. chalconota (Schlegel), R. raniceps (Peters) and R. labialis Boulenger. We describe four others as new species and suggest the existence of one or two additional, unnamed species. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 123–147.  相似文献   

20.
Smilacaceae, composed of Smilax and Heterosmilax, are a cosmopolitan family of > 200 species of mostly climbing monocots with alternate leaves characterized by reticulate venation, a pair of petiolar tendrils and usually prickly stems. Although there has been a long history of studying Smilax since Linnaeus named the genus in 1753, the phylogenetic history of this dioecious family remains unclear. Here we present results based on nuclear ribosomal internal transcribed spacer (nrITS) and plastid matK and rpl16 intron DNA sequence data from 125 taxa of Smilacaceae. Our taxon sampling covers all sections of Smilax and Heterosmilax and major distribution zones of the family; species from Ripogonaceae and Philesiaceae are used as outgroups. Our molecular analysis indicates that phylogenetic relationships largely contradict the traditional morphological classification of the family, instead showing a conspicuous geographical pattern among the species clades. The previously recognized genus Heterosmilax was found to be embedded in Smilax. Species in the family are separated into primarily New World and Old World clades, except for a single species lineage, Smilax aspera, that is sister to the remaining species of the family, but with poor statistical support. Ancestral character state reconstructions and examination of distribution patterns among the clades provide important information for future taxonomic revisions and historical biogeography of the group. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 535–548.  相似文献   

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