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1.
Twenty‐six strains morphologically identified as Cylindrospermum as well as the closely related taxon Cronbergia siamensis were examined microscopically as well as phylogenetically using sequence data for the 16S rRNA gene and the 16S‐23S internal transcribed spacer (ITS) region. Phylogenetic analysis of the 16S rRNA revealed three distinct clades. The clade we designate as Cylindrospermum sensu stricto contained all five of the foundational species, C. maius, C. stagnale, C. licheniforme, C. muscicola, and C. catenatum. In addition to these taxa, three species new to science in this clade were described: C. badium, C. moravicum, and C. pellucidum. Our evidence indicated that Cronbergia is a later synonym of Cylindrospermum. The phylogenetic position of Cylindrospermum within the Nostocaceae was not clearly resolved in our analyses. Cylindrospermum is unusual among cyanobacterial genera in that the morphological diversity appears to be more evident than sequence divergence. Taxa were clearly separable using morphology, but had very high percent similarity among ribosomal sequences. Given the high diversity we noted in this study, we conclude that there is likely much more diversity remaining to be described in this genus.  相似文献   

2.
The delimitation of the invasive moss species Campylopus introflexus from its closest relative, Campylopus pilifer, has been long debated based on morphology. Previous molecular phylogenetic reconstructions based on the nuclear ribosomal internal transcribed spacers (ITS) 1 and 2 showed that C. pilifer is split into an Old World and a New World lineage, but remained partly inconclusive concerning the relationships between these two clades and C. introflexus. Analyses of an extended ITS dataset displayed statistically supported incongruence between ITS1 and ITS2. ITS1 separates the New World clade of C. pilifer from a clade comprising C. introflexus and the Old World C. pilifer. Ancestral state reconstruction showed that this topology is morphologically supported by differences in the height of the dorsal costal lamellae in leaf cross‐section (despite some overlap). ITS2, in contrast, supports the current morphological species concept, i.e., separating C. introflexus from C. pilifer, which is morphologically supported by the orientation of the hyaline hair point at leaf apex as well as costal lamellae height. Re‐analysis of published and newly generated plastid atpB‐rbcL spacer sequences supported the three ITS lineages. Ecological niche modeling proved a useful approach and showed that all three molecular lineages occupy distinct environmental spaces that are similar, but undoubtedly not equivalent. In line with the ITS1 topology, the C. pilifer lineage from the New World occupies the most distinct environmental niche, whereas the niches of Old World C. pilifer and C. introflexus are very similar. Taking the inferences from ecological niche comparisons, phylogenetics, and morphology together, we conclude that all three molecular lineages represent different taxa that should be recognized as independent species, viz. C. introflexus, C. pilifer (Old World clade), and the reinstated C. lamellatus Mont. (New World clade).  相似文献   

3.
Less than 1% of Staphylinidae are known to be confined to coastal habitats. To explore the origins of coastal colonization within the tribe Athetini Casey, we present a revised molecular phylogeny. The dataset comprised partial mitochondrial COI, COII, 16S rDNA, NADH1, partial nuclear 18S rDNA and 28S rDNA. We chose a total of 95 species in 51 genera, including 14 coastal species in eight genera and 21 outgroup species from other aleocharine tribes. The concatenated dataset was analysed simultaneously by both parsimony‐ and model‐based (Bayesian and maximum likelihood) methods. The tribe Athetini was not supported as a monophyletic group, but together with the tribes Tachyusini, Ecitocharini and Hygronomini did form a monophylum. The ecological association of species with a coastal habitat was mapped onto a phylogeny to assess the evolution of habitat specialization in the Athetini lineage. The results reveal that five independent origins of coastal colonization have occurred throughout the tribe Athetini: (a) Osakatheta + Adota minuta + coastal Atheta (Badura) (clade A); (b) Adota (clade B); (c) Pontomalota + Tarphiota + Thinusa (clade C); (d) Iotarphia (clade D); and (e) Psammostiba (clade E). The low species number of the coastal Athetini compared with the entire Athetini lineage indicates that coastal habitats are harsh environments and so only a few species were able to colonize this habitat. The following changes in classification are proposed: (a) Ad. minuta Lee and Ahn is removed from the genus Adota and tentatively included in Atheta (Badura); (b) The genus Saphocallus Sharp is transferred from Athetini to Geostibini.  相似文献   

4.
Phylogenetic relationships among 36 Recent and 42 extinct species of the Caninae (Canidae) were analysed, based on 360 morphological, developmental, ecological, behavioural and cytogenetic characters and 24 mitochondrial and nuclear markers. Primary phylogenetic analyses were accompanied by experimental analyses based on various combinations of data partitions and taxon samples. Leptocyon was recovered as a paraphyletic stem lineage of the Caninae; monophyly/paraphyly of the fox‐like canids (Vulpini) remains uncertain; Urocyon and Metalopex form a clade, possibly sister to all non‐Leptocyon canids; Otocyon, Nyctereutes and Nurocyon form a clade; dog‐like canids (Canini) are monophyletic (with South American Cerdocyonina and Afro‐Holarctic Canina); all South American hypercarnivores (Canis gezi, Protocyon, Speothos, Theriodictis) form a clade, close to Chrysocyon and Dusicyon; Canis arnensis, C. ferox, C. thooides, C. lepophagus and Eucyon spp. are basal to the Canina; Lycaon is an isolated African hypercarnivore; Cuon and its relatives (Xenocyon, possibly also Canis antonii, C. falconeri and Cynotherium) form a clade close to Canis s. str.; C. edwardii–C. etruscus–C. mosbachensis–C. palmidens–C. variabilis and hypercarnivorous Canis armbrusteri–C. dirus clades belong to Canis s. str. As the highly homoplastic morphological characters connected to dietary biology are the prominent characters available for the key fossil species, we conclude that macroevolutionary and palaeoecological analyses of the extinct and extant Caninae were to some extent compromised by the phylogenies used.  相似文献   

5.
Cochliopodium is a lens‐shaped genus of Amoebozoa characterized by a flexible layer of microscopic dorsal scales. Recent taxonomic and molecular studies reported cryptic diversity in this group and suggested that the often‐used scale morphology is not a reliable character for species delineation in the genus. Here, we described three freshwater Cochliopodium spp. from the southeastern United States based on morphological, immunocytochemistry (ICC), and molecular data. A maximum‐likelihood phylogenetic analysis and pairwise comparison of COI sequences of Cochliopodium species showed that each of these monoclonal cultures were genetically distinct from each other and any described species with molecular data. Two of the new isolates, “crystal UK‐YT2” (Cochliopodium crystalli n. sp.) and “crystal‐like UK‐YT3” (C. jaguari n. sp.), formed a clade with C. larifeili, which all share a prominent microtubule organizing center (MTOC) and have cubical‐shaped crystals. The “Marrs Spring UK‐YT4” isolate, C. marrii n. sp., was 100% identical to “Cochliopodium sp. SG‐2014 KJ569724 .” These sequences formed a clade with C. actinophorum and C. arabianum. While the new isolates can be separated morphologically, most of the taxonomic features used in the group show plasticity; therefore, Cochliopodium species can only be reliably identified with the help of molecular data.  相似文献   

6.
A putative new limpet species (Patellogastropoda) from the Sea of Japan is revealed by molecular genetic analyses using the mitochondrial markers 16S rRNA and cytochrome c oxidase subunit I (CO1), as well as the DNA marker 18SrRNA. Our data indicate that the limpet, collected in the Peter the Great Bay (Russian Federation), is not, as its morphology suggests, the Japanese species Lottia kogamogaiSasaki and Okutani, 1994, and might also hint towards another putative species complex in the Sea of Japan. The different currents between the Far East Asian mainland (cold, subpolar jet running southwards) and the Japanese archipelago (warm, subtropical jet running northwards) are likely to act as a barrier that has a substantial influence on species distribution in these waters. Accordingly, our results indicate that it is about time for a revision of patellogastropod species with a reported distribution in Japanese and Far Eastern Russian waters by an integrative approach using molecular genetic and morphological characters. The species investigated herein is referred to as Lottia cf. kogamogai until it is morphologically re‐examined and compared with primary type specimens of known species.  相似文献   

7.
Based on multilocus phylogenetic analyses (18S, 28S, EF1‐α, SRP54, HSP70, CO1, 10 860 nt aligned), we show that the house dust mite subfamily Guatemalichinae is nested within non‐onychalgine pyroglyphid mites and forms the sister group to the genus Sturnophagoides (bootstrap support 100, posterior probability 1.0). Because high bootstrap support values may be misleading in the presence of incongruence, we evaluate robustness of the Guatemalichinae+Sturnophagoides clade using: (1) internode certainty indices to estimate the frequency of conflicting bipartitions in maximum‐likelihood bootstrap trees, (ii) consensus networks to investigate conflict among different loci; and (iii) statistical hypothesis testing based on information theory, both multi‐scale and regular bootstrap. Results suggest that this grouping is very well supported given the data. The molecular analyses were integrated with detailed morphological study using scanning electron and light microscopy. We suggest that the subfamilial status of Guatemalichinae should be reconsidered, and this lineage should be placed within the subfamily Dermatophagoidinae. The latter subfamily is currently accepted in the literature as a monophyletic group but was here inferred as paraphyletic and was not supported by any morphological synapomorphy. The paraphyly involved the most species‐rich and medically important genus, Dermatophagoides. Our findings suggest the need for a comprehensive revision of the higher‐level relationships of pyroglyphid house dust mites using both DNA sequences and morphology coupled with a broad taxonomic sampling.  相似文献   

8.
We investigated the species trees, temporal divergence and historical biogeography of Emplenota Casey and Triochara Bernhauer (ET clade hereafter), subgenera of the Aleochara coastal staphylinid beetles, to determine their place of origin. We explored a multilocus dataset to infer gene trees and species trees based on traditional concatenated and multispecies coalescent‐based approaches using both model‐ (maximum likelihood and Bayesian) and parsimony‐based methods. The multilocus dataset comprised DNA sequences from five nuclear genes (ArgK, CAD, EF1‐α, wg and 28S) and three mitochondrial genes (COI, COII and 16S). *BEAST analysis according to a coalescent‐based approach resolved the following phylogenetic relationships: ((Atrisulcata (Anubis Azerchei)) (Aobscurella ((Apacifica (Acurtidens + A. litoralis)) (Ahayamai (Ayamato (Afucicola (Asegregata Apuetzi))))))). Using a relaxed molecular clock, we reconstructed a time‐calibrated phylogeny for this group. Furthermore, to account for the historical biogeography of the ET clade at the ages of major divergences, we investigated the ancestral area based on a time‐calibrated phylogeny. Biogeographical analyses suggested that the ancestor of the ET clade was widely distributed along the eastern and western Palearctic and the western Nearctic coasts in the early Miocene. According to reconstruction of the ancestral area, one dispersal and three vicariance events were required, and the analyses indicated that vicariance events were important in shaping its current distribution patterns. Most of the divergence events occurred in the late Miocene and early Pliocene along the Pacific coasts, and the East Asian seacoasts harboured the most species‐rich fauna, including eight of the 13 species in the ET clade.  相似文献   

9.
10.
The freshwater red algal genus Batrachospermum has been shown to be paraphyletic since the first molecular studies of the Batrachospermales. Previous research, along with this study, provides strong support for the clade Batrachospermum section Helminthoidea. This study has found that heterocortication, the presence of both cylindrical and bulbous cells on the main axis, is an underlying synapomorphy of this clade. Based on support from DNA sequences of the rbcL gene, the COI barcode region and the rDNA ITS 1 and 2, along with morphological studies, the new genus Sheathia is proposed. Seven heterocorticate species were recognized from the molecular clades. Sheathia boryana and S. exigua sp. nov. appear to be restricted to Europe, whereas S. confusa occurs in Europe and New Zealand. Sheathia involuta is widespread in the USA and reported for the first time from Europe. Sheathia americana sp. nov., has been collected in the USA and Canada, and S. heterocortica and S. grandis sp. nov. have been collected only in the USA. Sheathia confusa and S. grandis can be distinguished based on morphological characters, whereas DNA sequence data are required to conclusively distinguish the other species. Sheathia fluitans and S. carpoinvolucra also are placed within this genus based on the presence of heterocortication. These data also hint at greater diversity among non‐heterocorticate Sheathia than is recognized by the single species name S. arcuata.  相似文献   

11.
Species of the genus Pleurodema are relatively small, plump frogs that mostly occur in strong‐seasonal and dry environments. The genus currently comprises 14 species distributed from Panama to southern Patagonia. Here we present a phylogenetic analysis of Pleurodema, including all described species and several outgroups. Our goals include testing its monophyly and the monophyly of the species groups that were historically proposed, and studying the evolution of some character systems, particularly macroglands and egg‐clutch structure; this last point also provided the chance for a discussion of foam nest evolution in anurans. Our dataset includes portions of the mitochondrial genes cytochromeb, 12S, 16S, and the intervening tRNAVal; the nuclear gene sequences include portions of rhodopsin exon 1 and seven in absentia homolog I. Our results support a clade composed of Pleurodema and including the monotypic Somuncuria Lynch, 1978 nested within it. The latter genus is therefore considered a junior synonym of Pleurodema and its sole species is added to this genus. Furthermore, our results indicate the non‐monophyly of several species groups proposed previously. We recognize four clades in Pleurodema: the P. bibroni clade (P. bibroni, P. cordobae and P. kriegi), the P. thaul clade (P. bufoninum, P. marmoratum, P. somuncurensis and P. thaul), the P. brachyops clade (P. alium, P. borellii, P. brachyops, P. cinereum, P. diplolister and P. tucumanum) and the P. nebulosum clade (P. guayapae and P. nebulosum). Our results further indicate the need for a taxonomic reassessment of P. borellii and P. cinereum (as did previous studies), P. guayapae and P. nebulosum, and the three species in the P. bibroni clade. Pleurodema shows a striking pattern of variation in presence/absence of lumbar glands. Our results indicate multiple losses or independent gains of this character associated with defensive displays. The reproductive modes of Pleurodema include four different egg‐clutch structures. The optimization of these indicates that there are at least two independent transformations from the plesiomorphic mode of foam nests to egg‐clutch structures involving gelatinous masses of different sorts (ovoid plates, masses, or strings). We hypothesize that these independent transformations could involve changes at the behavioural (the loss of foam beating behaviour by the parent) and/or structural level (transformations involving the pars convoluta dilata, the section of the oviduct where the foam‐making substance is secreted). Finally, our study of foam nest evolution in Pleurodema is extended to the other groups of anurans where foam‐nesting occurs, on the basis of available data and recent phylogenetic hypotheses. In the different hyloid groups where it occurs, foam‐nesting evolved from clutches laid in water. However, in all ranoids in which foam‐nesting occurs, it evolved from terrestrial clutches, with eggs laid hanging in vegetation, or, if the clutches are laid on a restricted volume of water, involving endotrophic development. © The Willi Hennig Society 2012.  相似文献   

12.
13.
Sivakumaran  Swarna  Bridge  Paul  Roberts  Peter 《Mycopathologia》2003,156(3):157-162
The three accepted species of Filobasidiella, F. neoformans, F. depauperata, and F. lutea, are compared morphologically and by molecular analysis. Sequences of the internally transcribed spacer (ITS) and the small subunit (SSU) gene of the ribosomal RNA (rRNA) gene cluster were obtained, and analysed by Neighbor-joining and Maximum parsimony methods. The three species of Filobsidiella are shown to form a single monophyletic clade, rooted by Tremella mesenterica. F. lutea was recovered as a distinct, but closely related taxon with the Filobasidiella clade. This is the first report of DNA sequences from herbarium specimens of F. lutea.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

14.
A new Phormidium‐like genus was found during an investigation of Oscillatoriales diversity in Brazil. Eight aerophytic populations from south and southeastern regions were isolated in monospecific cultures and submitted to polyphasic evaluation. The populations presented homogeneous morphology with straight trichomes, not attenuated, and apical cell with thickened cell wall. Phylogenetic analyses based on 16S rRNA gene sequences showed that these populations, plus the Brazilian strain Phomidium sp. B‐Tom from GenBank, formed a highly supported and distinctive clade, which corresponds to the new genus Pycnacronema, comprising six new species: P. brasiliensis (type species), P. arboriculum, P. conicum, P. marmoreum, P. rubrum, and P. savannensis. These results were confirmed and supported by rpoC1 and rbcL genes evaluated independently and by the concatenated analysis of 16S rRNA, rpoC1 and rbcL genes (for all species but P. savannensis). Secondary structures of the D1‐D1′, box‐B, and V3 regions of the internal transcribed spacer were informative at specific level, being conserved in P. brasiliensis and variable among the other strains, also confirming the phylogenetic analyses. The generic name and specific epithets of the new taxa are proposed under the provisions of the International Code of Nomenclature of algae, fungi, and plants.  相似文献   

15.
Our phylogenetic analysis of three endemic species of the Australian tiger beetle genus Pseudotetracha (Fleutiaux, 1864) from South Australia used sequences of two fragments of the mitochondrial genes 16S rRNA and cytochrome oxidase III. A matrix for each gene and two combined matrices were constructed. We compared these three riparian species, together with data from nine taxa of this genus available in GenBank, using parsimony and Bayesian methods. These molecular results are in agreement with the phylogenetic hypothesis for the blackburni/murchisona species complex previously proposed based on morphology, whereas other recent molecular analyses have questioned the existence of this species complex. In all of our analyses, samples of P. blackburni divided into two statistically supported clades, one of which is more closely related to P. mendacia and P. pulchra than to the other P. blackburni clade. This suggests the existence of a cryptic new species. Additionally, we analysed chromosomes of the second metaphase cells of members of the two clades. The observations showed different karyotypes as blackburni‐1 has two types of second meiotic metaphase cells with 11 and 12 chromosomes, whereas in blackburni‐2, all cells have 12 chromosomes, adding evidence for the putative existence of two species.  相似文献   

16.
We examined the hypothesis that genotypic variation among populations of commonly co‐occurring phreatophytic trees (Populus fremontii, Salix gooddingii) and the shrub (Salix exigua) regulates aboveground net primary productivity (ANPP) at a hot site at the edge of the species’ distribution. We used a provenance trial in which replicated genotypes from populations varying in mean annual temperature were transplanted to a common garden adjacent to the Lower Colorado River in southeastern California. The garden environment represented an extreme maximum temperature for the study species. Four major findings emerged: (1) Genotypic variation in ANPP was significant for all species with broad‐sense heritability (H2) across populations of 0.11, 0.13, and 0.10 for P. fremontii, S. gooddingii, and S. exigua, respectively, and within‐population H2 ranging from 0.00 to 0.25, 0.00 to 0.44, and 0.02 to 0.21, respectively. (2) Population ANPP decreased linearly as mean annual maximum temperature (MAMT) transfer distance increased for both P. fremontii (r2 = 0.64) and S. gooddingii (r2 = 0.37), whereas it did not change for S. exigua; (3) Populations with similar MAMT to that of the common garden were 1.5 and 1.2 times more productive than populations with 5.0 °C MAMT transfer distances for P. fremontii and S. gooddingii, respectively; and (4) Variation in regression slopes among species for the relationship between ANPP and MAMT indicate species‐specific responses to temperature. As these plant species characterize a threatened habitat type and support a diverse community that includes endangered species, ecosystem restoration programs should consider using both local genotypes and productive genotypes from warmer environments to maximize productivity of riparian ecosystems in the face of global climate change.  相似文献   

17.
Seventy‐five diatom strains isolated from the Beaufort Sea (Canadian Arctic) in the summer of 2009 were characterized by light and electron microscopy (SEM and TEM), as well as 18S and 28S rRNA gene sequencing. These strains group into 20 genotypes and 17 morphotypes and are affiliated with the genera Arcocellulus, Attheya, Chaetoceros, Cylindrotheca, Eucampia, Nitzschia, Porosira, Pseudo‐nitzschia, Shionodiscus, Thalassiosira, and Synedropsis. Most of the species have a distribution confined to the northern/polar area. Chaetoceros neogracilis and Chaetoceros gelidus were the most represented taxa. Strains of C. neogracilis were morphologically similar and shared identical 18S rRNA gene sequences, but belonged to four distinct genetic clades based on 28S rRNA, ITS‐1 and ITS‐2 phylogenies. Secondary structure prediction revealed that these four clades differ in hemi‐compensatory base changes (HCBCs) in paired positions of the ITS‐2, suggesting their inability to interbreed. Reproductively isolated C. neogracilis genotypes can thus co‐occur in summer phytoplankton communities in the Beaufort Sea. C. neogracilis generally occurred as single cells but also formed short colonies. It is phylogenetically distinct from an Antarctic species, erroneously identified in some previous studies as C. neogracilis, but named here as Chaetoceros sp. This work provides taxonomically validated sequences for 20 Arctic diatom taxa, which will facilitate future metabarcoding studies on phytoplankton in this region.  相似文献   

18.
The present molecular systematic and phylogeographic analysis is based on sequences of cytochrome c oxidase subunit 1 (cox1) (mtDNA) and 28S ribosomal DNA and includes 59 isolates of cestodes of the genus Anoplocephaloides Baer, 1923 s. s. (Cyclophyllidea, Anoplocephalidae) from arvicoline rodents (lemmings and voles) in the Holarctic region. The emphasis is on Anoplocephaloides lemmi (Rausch 1952) parasitizing Lemmus trimucronatus and Lemmus sibiricus in the northern parts of North America and Arctic coast of Siberia, and Anoplocephaloides kontrimavichusi (Rausch 1976) parasitizing Synaptomys borealis in Alaska and British Columbia. The cox1 data, 28S data and their concatenated data all suggest that A. lemmi and A. kontrimavichusi are both non‐monophyletic, each consisting of two separate, well‐defined clades, that is independent species. As an example, the sister group of the clade 1 of A. lemmi, evidently representing the ‘type clade’ of this species, is the clade 1 of A. kontrimavichusi. For A. kontrimavichusi, it is not known which one is the type clade. There is also fairly strong evidence for the non‐monophyly of Anoplocephaloides dentata (Galli‐Valerio, 1905)‐like species, although an earlier phylogeny suggested that this multispecies assemblage may be monophyletic. The results suggest a deep phylogenetic codivergence of Lemmus spp. and A. lemmi, primarily separating the two largely allopatric host and parasite species at the Kolyma River in east Siberia. There are also two allopatric sublineages within each main clade/species of A. lemmi and Lemmus, but the present distributions of the sublineages within the eastern L. trimucronatus and clade 1 of A. lemmi are not concordant. This discrepancy may be most parsimoniously explained by an extensive westward distributional shift of the easternmost parasite subclade. The results further suggest that the clade 1 of A. kontrimavichusi has diverged through a host shift from the precursor of L. trimucronatus to S. borealis.  相似文献   

19.
Relative to its diversity (34 genera, 700 species), Scolopendromorpha has been undersampled in molecular phylogenetic analyses compared with the other chilopod orders. Previous analyses based on morphology have not resolved several key controversies in systematics and evolutionary morphology unambiguously. Here we apply new molecular and morphological data to scolopendromorph phylogenetics, with a focus on the evolution of blindness. The taxonomic sample includes 19 genera, many lacking previous molecular data, and diverse, cosmopolitan genera of Scolopendridae are sampled by multiple species. Phylogenetic analysis with Direct Optimization used 94 morphological characters and ca. 4.5 kb of sequence data from two nuclear (18S and 28S rRNA) and two mitochondrial (16S rRNA and COI) loci. A single most‐parsimonious cladogram selected after sensitivity analyses resolves Scolopendromorpha as monophyletic, and divides it into a blind clade of three families (Plutoniumidae, Cryptopidae, Scolopocryptopidae) and its ocellate sister group, Scolopendridae. Some species‐rich, cosmopolitan genera (Cormocephalus, Otostigmus, Scolopendra) in Scolopendridae are non‐monophyletic, and in several instances (e.g. New and Old World Scolopendra) relationships are more congruent with geographical distributions than with traditional classifications. The tribe Asanadini is particularly subject to parameter‐sensitivity, nesting in the combined analysis within Scolopendrini but as sister to all other Scolopendrinae for molecular data alone. The total‐evidence tree unambiguously optimizes trunk segmentation: a 23‐segmented trunk has a single origin in the blind clade. © The Willi Hennig Society 2011.  相似文献   

20.
The taxonomy of the endemic arboreal snail Satsuma albida species complex from Taiwan was unclear due to the animals' highly similar morphology, and their nocturnal and strict arboreal behaviour, leading to difficulties in collecting living specimens. This article is the first comprehensive comparative study on the systematics and taxonomy of this species complex using external morphology, anatomy of the reproductive system and molecular phylogeny. Consequently, two subspecies of S. albida are raised to species status, namely S. insignis and S. mollicula. Fourteen new species are also described. Fourteen of the 17 species showed polymorphism in banding pattern amongst populations and other species retained the whitish unity as seen in S. albida. Distributions of almost all taxa are geographically limited, with the exception of S. polymorpha sp. nov . The phylogeny of these species was reconstructed using 20 morphological characters and molecular data from the partial sequences of mtDNA CO1 and 16S rRNA genes, and the complete ITS2 sequence. The molecular phylogeny revealed three subclades (west, east and polymorpha clade) and revealed that these snails are monophyletic, originating from a ground‐dwelling ancestor. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 437–493.  相似文献   

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