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The phylogenetic relationships among genera of the subfamily Ariantinae (Pulmonata, Helicidae), especially the sister‐group relationship of Cylindrus obtusus, were investigated with three mitochondrial (12S rRNA, 16S rRNA, Cytochrome c oxidase subunit I) and two nuclear marker genes (Histone H4 and H3). Within Ariantinae, C. obtusus stands out because of its aberrant cylindrical shell shape. Here, we present phylogenetic trees based on these five marker sequences and discuss the position of C. obtusus and phylogeographical scenarios in comparison with previously published results. Our results provide strong support for the sister‐group relationship between Cylindrus and Arianta confirming previous studies and imply that the split between the two genera is quite old. The tree reveals a phylogeographical pattern of Ariantinae with a well‐supported clade comprising the Balkan taxa which is the sister group to a clade with individuals from Alpine localities. Additional lineages representing samples from southern Alpine localities as well as from Slovakia split from more basal nodes, but their relationships are not clearly resolved. To achieve more definitive conclusions concerning the geographical origin of Ariantinae, still more sequence data are needed to obtain a tree with better resolution of basal nodes. The genetic data also provided new insights concerning the genus Cepaea, which was used as one of the outgroup taxa. Cepaea vindobonensis is only distantly related to Cepaea nemoralis and Cepaea hortensis, the latter two being more closely related to Eobania vermiculata. Thus, in our tree, the genus Cepaea is paraphyletic.  相似文献   

3.
Although only a small fraction of the estimated 6000 extant bryozoan species has been analysed in a molecular phylogenetic context, the resultant trees have increased our understanding of the interrelationships between major bryozoan groups, as well as between bryozoans and other metazoan phyla. Molecular systematic analyses have failed to recover the Lophophorata as a monophyletic clade until recently, when phylogenomic data placed the Brachiopoda as sister to a clade formed by Phoronida + Bryozoa. Among bryozoans, class Phylactolaemata has been shown to be the sister group of Gymnolaemata + Stenolaemata, corroborating earlier anatomical inferences. Despite persistent claims, there are no unequivocal bryozoans of Cambrian age: the oldest bryozoans are stenolaemates from the Tremadocian of China. Stenolaemates underwent a major radiation during the Ordovician, but the relationships between the six orders involved are poorly understood, mostly because the simple and plastic skeletons of stenolaemates make phylogenetic analyses difficult. Bryozoans were hard‐hit by the mass extinction/s in the late Permian and it was not until the Middle Jurassic that they began to rediversify, initially through the cyclostome stenolaemates. The most successful post‐Palaeozoic order (Cheilostomata) evolved a calcareous skeleton de novo from a soft‐bodied ancestor in the Late Jurassic, maintained a low diversity until the mid‐Cretaceous and then began to radiate explosively. A remarkable range of morphological structures in the form of highly modified zooidal polymorphs, or non‐zooidal or intrazooidal modular elements, is postulated to have evolved repeatedly in this group. Crucially, many of these structures have been linked to micropredator protection and can be interpreted as key traits linked to the diversification of cheilostomes.  相似文献   

4.
分子系统学研究将传统梧桐科与锦葵科、木棉科和椴树科合并为广义锦葵科,并进一步分为9个亚科.然而,9个亚科之间的关系尚未完全明确,且梧桐亚科内的属间关系也未得到解决.为了明确梧桐亚科在锦葵科中的系统发育位置,厘清梧桐亚科内部属间系统发育关系,该研究对锦葵科8个亚科进行取样,共选取55个样本,基于叶绿体基因组数据,采用最大...  相似文献   

5.
The tribe Diochini has a worldwide distribution, with 2 and 74 epigean species within the genera Antarctothius and Diochus, respectively. Recent phylogenetic studies suggest a sister relationship of Diochini and a lineage formed by Xantholinini, Maorothiini, and Othiini, within the subfamily Staphylininae. Here, we describe the first known endogean representative of Diochini, Diochus occultus n. sp., and provide the first two complete mitogenomes for the tribe, corresponding to the two European Diochus species: Diochus occultus n. sp. and Diochus staudingeri. These sequences were combined with 40 additional mitogenomes from representatives within Staphylininae, Paederinae, Silphidae, and Aleocharinae, and COI sequences from 5 additional species of Diochus to conduct a series of mitogenomic phylogenetic and dating analyses. The estimated molecular phylogeny is fully consistent with previous studies based on morphology and molecular data, finding a sister relationship of Diochini with a clade formed by Xantholinini and Othiini (Maorothiini not sampled). Dating analyses inferred an early split of the tribe Diochini at 140–156 Mya. Morphology shows clear differences in the aedeagal and external morphology of D. occultus n. sp. and D. staudingeri, whereas a sister relationship of these taxa is found in the phylogenetic analyses, with the split dated at 48–61 Mya. Although the study of additional Palaearctic Diochus species will be required to conclusively establish that D. occultus n. sp. is a palaeoendemic taxon sister to D. staudingeri, associated with forests of Abies pinsapo in the south of the Iberian Peninsula, this conclusion is consistent with the ancient estimated age of speciation, endogean habitat specificity, low dispersal capacity (flightless species), and microendemicity of D. occultus. This is also consistent with the continued emersion of the Betic sub‐plate along its tectonic evolution. The estimated ages of diversification of the Paederinae‐Staphylininae lineage are also discussed.  相似文献   

6.
The Rufous‐headed Robin Larvivora ruficeps is one of the world's rarest and least known birds. We summarize the known records since it was first described in 1905 from Shaanxi Province, central China. All subsequent Chinese records are from seven adjacent localities in nearby Sichuan Province. We studied its phylogenetic position for the first time using mitochondrial and nuclear markers for all species of Larvivora and a broad selection of other species in the family Muscicapidae. Our results confirmed that L. ruficeps is appropriately placed in the genus Larvivora, and suggested that it is sister to the Rufous‐tailed Robin Larvivora sibilans, with these two forming a sister clade to a clade comprising both the Japanese Robin Larvivora akahige and Ryukyu Robin Larvivora komadori. Siberian Blue Robin Larvivora cyane and Indian Blue Robin Larvivora brunnea form the sister clade to the other Larvivora species. In contrast, song analyses indicated that the song of L. ruficeps is most similar to that of L. komadori, whereas the song of L. sibilans is relatively more similar to that of L. akahige, and songs of L. cyane and L. brunnea closely resemble each other. We used ecological niche modelling to estimate the suitable habitats of L. ruficeps based on the records from breeding grounds, suggesting that north and central Sichuan, south Gansu, south Shaanxi and south‐east Tibet are likely to contain the most suitable habitats for this species.  相似文献   

7.
Here, we established the cyst‐motile stage relation‐ship for Spiniferites pachydermus through incubation of cysts with a characteristically microreticulate/perforate surface isolated from Izmir Bay in the eastern Aegean Sea of the eastern Mediterranean. The morphology of the motile stage was similar to Gonyaulax spinifera but had a different size, overhang, displacement and reticulations. Based on the distinct morphology of the cyst and morphological differences in motile cells, we assigned S. pachydermus from Izmir Bay to the new species Gonyaulax ellegaardiae. We elucidate the phylogenetic relationship of G. ellegaardiae through large and small subunit ribosomal DNA and show that it forms a clade with other species that belong to the G. spinifera complex.  相似文献   

8.
The Northern Goshawk Accipiter gentilis is a medium‐sized bird of prey inhabiting boreal and temperate forests. It has a Holarctic distribution with 10 recognized subspecies. Traditionally, it has been placed within the Accipiter [gentilis] superspecies, together with Henst's Goshawk A. henstii, the Black Sparrowhawk A. melanoleucus, and Meyer's Goshawk A. meyerianus. While those four taxa are geographically separated from each other, hence referred to as allospecies, their phylogenetic relationships are still unresolved. In the present study, we performed phylogenetic analyses on the Accipiter [gentilis] superspecies, including all recognized subspecies of all four allospecies, using partial sequences of two marker loci of the mitochondrial genome, the control region and the cytochrome b gene. We found a deep split within A. gentilis into two monophyletic groups, a Nearctic clade (three subspecies) and a Palearctic clade (seven subspecies). The Palearctic clade is closely related to A. meyerianus, and together these two were more closely related to the other Old World taxa A. henstii and A. melanoleucus, which in turn were reciprocally monophyletic sister species. As a consequence, A. gentilis as usually conceived (including all Holarctic subspecies) was non‐monophyletic. We found a strong genetic homogeneity within Palearctic A. gentilis despite the fact that it comprises seven subspecies distributed from the Atlantic coast in Western Europe to Eastern Siberia. Relationships between the four clades could not be resolved unambiguously. Our results, if confirmed by more integrative data, would imply a taxonomic revision of Nearctic A. gentilis into a separate allospecies, Accipiter [gentilis] atricapillus.  相似文献   

9.
Chicken repeat 1 (CR1), a member of non‐LTR retroposon, is an important phylogenetic marker in avian systematics. In this study, we reported several characteristics of CR1 elements in a draft genome of Arborophila rufipectus (Sichuan partridge). According to the analyses of RepeatMasker, approximately 254 966 CR1 elements were identified in A. rufipectus, covering 6.7% of the genome. Subsequently, we selected eighteen novel CR1 elements by comparing the chicken genome, turkey genome and assembled A. rufipectus scaffolds. Here, a combined data set comprising of 22 CR1 loci, mitochondrial genomes and eight unlinked introns was analysed to infer the evolutionary relationships of twelve Phasianidae species. The applicability of CR1 sequences for inferring avian phylogeny relative to mtDNA and intron sequences was investigated as well. Our results elucidated the position of A. rufipectus in Phasianidae with robust supports that it presented a sister clade to Arborophila ardens/Arborophila brunneopectus, and implied that genus Arborophila was in a basal phylogenetic position within Phasianidae and a phylogenetic affinity between Meleagris gallopavo and Pucrasia macrolopha. Therefore, this work not only resolved some of the confounding relationships among Phasianidae, but also suggested CR1 sequences could provide powerful complementary data for phylogeny reconstruction.  相似文献   

10.
We performed a phylogenetic analysis using nuclear (RAG‐1, RAG‐2) and mitochondrial (16S) markers, a statistical Bayesian reconstruction of ancestral distribution areas and a karyological analysis on most Malagasy species of the gekkonid genus Lygodactylus. The phylogenetic analysis largely confirms major basal branching pattern of previous molecular studies, but highlights significant differences concerning both the relationships between different species groups as well as those within groups. The biogeographic analysis supports a Malagasy origin of Lygodactylus, an oversea dispersal to continental Africa and a return to Madagascar. The L. madagascariensis group (also including a new candidate species identified herein) is the most basal clade in Lygodactylus, and the sister group of a clade with all the remaining species. The second most basal clade is the L. verticillatus group, placed as the sister group of a clade comprising African and Malagasy species. The sister lineage of the L. verticillatus group originated the African radiation through an oversea dispersal out of Madagascar. Eventually, the sister lineage of the L. capensis group originated secondary dispersals from Africa to Madagascar. In Madagascar, lineage diversification in different species groups mainly occurred from southern to northern and eastern regions. Dispersal, vicariance and paleoclimatic refugia probably played a relevant role in the evolutionary history of closely related taxa and in speciation mechanisms. The cytogenetic analysis evidenced a high karyotypic variability in Lygodactylus (from 2n = 34 to 2n = 40), which is at least partly consistent with the phylogenetic relationships and the composition of the various species group. Chromosome evolution occurred independently in different lineages, mainly through a reduction in the chromosome number and starting from a putative primitive karyotype of 2n = 40 with all telocentric elements.  相似文献   

11.
We provide a taxonomic review of the extinct testudinid Testudo catalaunica, based on published and unpublished material from several Miocene (late Aragonian and early Vallesian) sites of the Vallès‐Penedès Basin (north‐east Iberian Peninsula). We show that Testudo catalaunica irregularis is a junior subjective synonym of T. catalaunica, and further provide an emended diagnosis of the latter based on newly reported material. Contrary to some recent suggestions, this emended diagnosis discounts an alternative attribution of T. catalaunica to Paleotestudo. The latter is merely recognized as a subgenus of Testudo, based on a cladistic analysis that assessed the phylogenetic position of all extant and most extinct species of Testudo currently recognized as valid (including T. catalaunica). Our phylogenetic analysis (which recovers the molecular phylogeny of extant Testudo s.l.) supports a taxonomic scheme in which the three extant subgenera of Testudo are represented in the fossil record. Testudo s.s. is retrieved as the sister taxon of Testudo (Agrionemys) + [Testudo (Paleotestudo) + Testudo (Chersine)]. The extinct Testudo (Paleotestudo) is therefore the sister taxon of the Testudo (Chersine) clade. The latter subgenus reveals as the most diverse clade of Testudo s.l. in the fossil record, with T. catalaunica Testudo steinheimensis constituting a subclade distinct from that including Testudo hermanni.  相似文献   

12.
Restriction site‐associated DNA sequencing (RAD‐seq) was used to illuminate the genetic relationships among Eriobotrya species. The raw data were filtered, and 221 million clean reads were used for further analysis. A total of 1,983,332 SNPs were obtained from 23 Eriobotrya species and two relative genera. We obtained similar results by neighbor‐joining and maximum likelihood phylogenetic trees. All Eriobotrya plants grouped together into a big clade, and two out‐groups clustered together into a single or separate clade. Chinese and Vietnam accessions were distributed throughout the dendrogram. There was nonsignificant correlation between genotype and geographical distance. However, clustering results were correlated with leaf size to some extent. The Eriobotrya species could be divided into following three groups based on leaf size and phylogenetic analysis: group A and group B comprised of small leaves with <10 cm length except E. stipularis (16.76 cm), and group C can be further divided into two subgroups, which contained medium‐size leaves with a leaf length ranged from 10 to 20 cm and a leaf length bigger than 20 cm.  相似文献   

13.
14.
Similar morphological characters and little molecular data of Amphioctopus rex, A. neglectus and A. cf. ovulum resulted in their unknown phylogenetic statuses and equivocal relationships. In this study, the complete mitochondrial genomes of these three species collected in Chinese waters were sequenced and compared with each other to clarify the relationships among them. The lengths of the mitochondrial genomes varied from 15,646 bp to 15,814 bp, and the A + T content and GC skew for protein‐coding genes showed little variation. In contrast, both a dendrogram based on codon usage and the gene arrangements of the three octopuses showed that A. rex was more closely related to A. neglectus than to A. cf. ovulum. Five data sets and two methods (maximum likelihood and Bayesian inference) were utilized for the first time to explore the phylogenetic relationships among these three species in Octopodidae. The results indicated that a data set combining protein‐coding genes and RNA genes (PR) was optimal for analysing the relationships among 43 cephalopods. All of the phylogenetic trees divided the cephalopods into 10 taxa and supported the monophyly of Oegopsida, Myopsida, Sepiidae and Octopodidae. In this study, Idiosepiidae was classified as sister to Sepiolidae. Trees constructed using all data sets robustly supported the monophyly of the genus Amphioctopus. Notably, A. rex was more closely related to A. neglectus than to A. cf. ovulum, although these three species share the characteristic of violet rings on dark ocelli.  相似文献   

15.
We studied the speciose butterfly genus Erebia by reconstructing its phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification for its lineages and employed a biogeographical analysis in order to reconstruct its evolutionary history. DNA sequence data from one mitochondrial gene and three nuclear genes were analyzed for a total of 74 species in Erebia. The estimated dates of origin and diversification for clades, in combination with a biogeographical analysis, suggest that the genus originated in Asian Russia and started its diversification process around 23 Myr. An important event was the dispersal of a lineage from Asia to Western Europe between 23 and 17 Myr, which allowed the radiation of most of species in the genus. The diversification pattern is consistent with a model of diversity limited by clade richness, which implies an early rapid diversification followed by deceleration due to a decrease in speciation. We argue that these characteristics of the evolutionary history of Erebia are consistent with a density‐dependent scenario, with species radiation limited by filling of niche space and reduced resources. We found that the Boeberia parmenio appears strongly supported in the genus Erebia and therefore we place Boeberia Prout, 1901 as a junior synonym of Erebia Dalman, 1816 ( syn. nov. ).  相似文献   

16.
To better understand organelle genome evolution of the ulvophycean green alga Capsosiphon fulvescens, we sequenced and characterized its complete chloroplast genome. The circular chloroplast genome was 111,561 bp in length with 31.3% GC content that contained 108 genes including 77 protein‐coding genes, two copies of rRNA operons, and 27 tRNAs. In this analysis, we found the two types of isoform, called heteroplasmy, were likely caused by a flip‐flop organization. The flip‐flop mechanism may have caused structural variation and gene conversion in the chloroplast genome of C. fulvescens. In a phylogenetic analysis based on all available ulvophycean chloroplast genome data, including a new C. fulvescens genome, we found three major conflicting signals for C. fulvescens and its sister taxon Pseudoneochloris marina within 70 individual genes: (i) monophyly with Ulotrichales, (ii) monophyly with Ulvales, and (iii) monophyly with the clade of Ulotrichales and Ulvales. Although the 70‐gene concatenated phylogeny supported monophyly with Ulvales for both species, these complex phylogenetic signals of individual genes need further investigations using a data‐rich approach (i.e., organelle genome data) from broader taxon sampling.  相似文献   

17.
The green anole (Anolis carolinensis) is a lizard widespread throughout the southeastern United States and is a model organism for the study of reproductive behavior, physiology, neural biology, and genomics. Previous phylogeographic studies of A. carolinensis using mitochondrial DNA and small numbers of nuclear loci identified conflicting and poorly supported relationships among geographically structured clades; these inconsistencies preclude confident use of A. carolinensis evolutionary history in association with morphological, physiological, or reproductive biology studies among sampling localities and necessitate increased effort to resolve evolutionary relationships among natural populations. Here, we used anchored hybrid enrichment of hundreds of genetic markers across the genome of A. carolinensis and identified five strongly supported phylogeographic groups. Using multiple analyses, we produced a fully resolved species tree, investigated relative support for each lineage across all gene trees, and identified mito‐nuclear discordance when comparing our results to previous studies. We found fixed differences in only one clade—southern Florida restricted to the Everglades region—while most polymorphisms were shared between lineages. The southern Florida group likely diverged from other populations during the Pliocene, with all other diversification during the Pleistocene. Multiple lines of support, including phylogenetic relationships, a latitudinal gradient in genetic diversity, and relatively more stable long‐term population sizes in southern phylogeographic groups, indicate that diversification in A. carolinensis occurred northward from southern Florida.  相似文献   

18.
Strix (Strigidae) is a worldwide genus of 17 owl species typical of forested habitats, including Rusty‐barred Owls (S. hylophila), Chaco Owls (S. chacoensis), and Rufous‐legged Owls (S. rufipes) in South America. These species are distributed allopatrically, but the ecological traits that determine their distributions remain largely unknown and their phylogenetic relationships are unclear. We used species distribution models (SDMs) to identify variables explaining their distribution patterns and test hypotheses about ecological divergence and conservatism based on niche overlap analysis. For Rusty‐barred Owls and Chaco Owls, climatic factors related to temperature played a major role, whereas a rainfall variable was more important for Rufous‐legged Owls. When niche overlaps were compared, accounting for regional similarities in the habitat available to each species, an ecological niche divergence process was supported for Chaco Owl‐Rusty‐barred Owl and Chaco Owl‐Rufous‐legged Owl, whereas a niche conservatism process was supported for Rusty‐barred Owl‐Rufous‐legged Owl. Different ecological requirements support current species delimitation, but they are in disagreement with the two main hypotheses currently envisaged about their phylogenetic relationships (Chaco Owls as the sister taxa of either Rufous‐legged Owls or Rusty‐barred Owls) and support a new phylogenetic hypothesis (Rufous‐legged Owls as sister taxa of Rusty‐barred Owls). Our findings suggest that speciation of Rusty‐barred Owls and Rufous‐legged Owls was a vicariant event resulting from Atlantic marine transgressions in southern South America in the Miocene, but their niche was conserved because habitat changed little in their respective ranges. In contrast, Chaco Owls diverged ecologically from the other two species as a result of their adaptations to the habitat they currently occupy. Ecological and historical approaches in biogeography can be embedded to explain distribution patterns, and results provided by SDMs can be used to infer historical and ecological processes in an integrative way.  相似文献   

19.
The monophyly of the Sceloporus variabilis group is well established with five species and two species complexes, but phylogenetic relationships within species complexes are still uncertain. We studied 278 specimens in 20 terminals to sample all taxa in the “variabilis group,” including three subspecies in the “variabilis complex,” and two outgroups (Sceloporus grammicus and Sceloporus megalepidurus). We assembled an extensive morphological data set with discrete and continuous characters (distances and scale counts), including geometric morphometric data (landmark coordinates of three shapes), and a three‐marker molecular data set as well (ND4, 12S and RAG1). We conducted parsimony and Bayesian phylogenetic inferences on these data, including several partitioning and weighting schemes. We suggest elevating three subspecies to full species status. Therefore, we recommend recognition of nine species in the “variabilis group.” First, S. variabilis is sister to Sceloporus teapensis. In turn, Sceloporus cozumelae is sister to Sceloporus olloporus. These four species are a monophyletic group, which is sister to Sceloporus smithi. Finally, Sceloporus marmoratus is sister of the clade of five species. The other species in the “variabilis group” (Sceloporus chrysostictus, Sceloporus couchii and Sceloporus parvus) are a paraphyletic grade at the base of the tree. Our analyses reject the existence of the “variabilis complex.” We conducted a parsimony‐based ancestral reconstruction on body size (snout–vent length), femoral pores and dorsal scales and related morphological changes to geographic distribution of the species. Our phylogenetic hypothesis will allow best designs of comparative studies with species in the “variabilis group,” one of the earliest divergent lineages in the genus.  相似文献   

20.
Prasinophytes are a paraphyletic assemblage of nine heterogeneous lineages in the Chlorophyta clade of Archaeplastida. Until now, seven complete mitochondrial genomes have been sequenced from four prasinophyte lineages. Here, we report the mitochondrial genome of Pyramimonas parkeae, the first representative of the prasinophyte clade I. The circular‐mapping molecule is 43,294 bp long, AT rich (68.8%), very compact and it comprises two 6,671 bp long inverted repeat regions. The gene content is slightly smaller than the gene‐richest prasinophyte mitochondrial genomes. The single identified intron is located in the cytochrome c oxidase subunit 1 gene (cox1). Interestingly, two exons of cox1 are encoded on the same strand of DNA in the reverse order and the mature mRNA is formed by trans‐splicing. The phylogenetic analysis using the data set of 6,037 positions assembled from 34 mtDNA‐encoded proteins of 48 green algae and plants is not in compliance with the branching order of prasinophyte clades revealed on the basis of 18S rRNA genes and cpDNA‐encoded proteins. However, the phylogenetic analyses based on all three genomic elements support the sister position of prasinophyte clades Pyramimonadales and Mamiellales.  相似文献   

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