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1.
The tribe Cercosaurini is one of the most poorly studied groups of the lizard family Gymnophthalmidae. Recent studies have suggested that two cercosauriine genera, Neusticurus and Proctoporus , are polyphyletic. The aim of the current study was to rectify the polyphyletic relationships and construct a phylogenetic taxonomy of the Cercosaurini that is congruent with evolutionary history. Neusticurus is divided into two genera, one of them new ( Potamites ), based on the clades recovered by molecular studies and previously discussed morphological data. Proctoporus is divided into three genera, one of which is new ( Petracola ), while an older name ( Riama ) is resurrected for another. All five genera are described and defined and taxonomic keys are presented. This study represents an important advance in rectifying the taxonomy of the Cercosaurini. Many other para- and polyphyletic genera remain in the Gymnophthalmidae and much future work on this group is warranted.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 405–416.  相似文献   

2.
Tribe Sabiceeae (Ixoroideae, Rubiaceae) has undergone recent taxonomical changes with the incorporation of the related genera Ecpoma, Pseudosabicea and Stipularia into the type genus Sabicea. We use phylogenetic analysis and morphological data to verify the relationships among members of the tribe, including the most comprehensive taxon sampling of the tribe to date with 74 of 145 species. Sequence data from the nuclear internal transcribed spacer (ITS) and three plastid markers (petD, rps16, trnT–F) were used to infer relationships among the members of the tribe. Individual analyses using maximum likelihood, parsimony and Bayesian approaches reveal several supported clades: the former genus Stipularia is resolved as a monophyletic unit, but Ecpoma is monophyletic only if Sabicea urbaniana and Sabicea xanthotricha are included (corresponding to Sabicea subgenus Stipulariopsis sensu Wernham). Pseudosabicea is biphyletic, with one clade corresponding to section Anisophyllae of Hallé (1964) and the other one to the other sections (Floribundae and Sphaericae) of the genus. Eleven morphological characteristics were recorded for all species studied and seven have been mapped onto the phylogenetic tree to study their evolution in the group and assess their value for the classification of Sabicea s.l. Finally, our study shows that a combination of diagnostic characteristics should be used to differentiate each group and we propose to recognise four subgenera in Sabicea.  相似文献   

3.
The subfamily Eneopterinae is known greatly for its diversified acoustic modalities and disjunct distribution. Within Eneopterinae, tribe Lebinthini is the most studied group, due to its highest species diversity (ca. 150 species in 12 genera), endemic distribution on the islands of Southeast Asia and of the South West Pacific, males’ ability to produce high‐frequency calling songs, and evolution of females’ vibrational response. To investigate the distribution pattern and diversification of acoustic and behavioral attributes in a larger frame, clear understanding of phylogenetic relationships within other tribes of Eneopterinae is vital. In this study, we focus on the tribe Xenogryllini, sister group of Lebinthini. Xenogryllini, as opposed to Lebinthini, is known by fewer species (11 species in two genera), distributed widely in continental Asia and Africa, and for producing low‐frequency calling songs. We describe a new genus Indigryllus with a new species of the tribe Xenogryllini, discovered from the southwest of India. We used eight molecular genetic markers to reconstruct the phylogenetic relationships. The resultant phylogenetic tree is used to compare and discuss distribution patterns and acoustic modalities between Lebinthini and Xenogryllini.  相似文献   

4.
Molecular assessment of a large portion of traditional cyanobacterial taxa has been hindered by the failure to isolate and grow them in culture. In this study, we developed an optimized protocol for single cell/filament isolation and 16S rRNA gene sequencing of terrestrial cyanobacteria with large mucilaginous sheaths, and applied it to determine the phylogenetic position of typical members of the genera Petalonema and Stigonema. A methodology based on a glass‐capillary isolation technique and a semi‐nested PCR protocol enabled reliable sequencing of the 16S rRNA gene from all samples analyzed. Ten samples covering seven species of Stigonema from Europe, North and Central America, and Hawaii, and the type species of Petalonema from Slovakia were sequenced. Contrary to some previous studies, which proposed a relationship with heteropolar nostocalean cyanobacteria, Petalonema appeared to belong to the family Scytonemataceae. Analysis of Stigonema specimens recovered a unique coherent phylogenetic cluster, substantially broadening our knowledge of the molecular diversity within this genus. Neither the uni‐ to biseriate species nor the multiseriate species formed monophyletic subclusters within the genus. Typical multiseriate species of Stigonema clustered in a phylogenetic branch derived from uni‐ to biseriate S. ocellatum Thuret ex Bornet & Flahault in our analysis, suggesting that species with more complex thalli may have evolved from the more simple ones. We propose the technique tested in this study as a promising tool for a future revision of the molecular taxonomy in cyanobacteria.  相似文献   

5.
Gracilariaceae are mostly pantropical red algae and include ~230 species in seven genera. Infrafamilial classification of the group has long been based on reproductive characters, but previous phylogenies have shown that traditionally circumscribed groups are not monophyletic. We performed phylogenetic analyses using two plastid (universal plastid amplicon and rbcL) and one mitochondrial (cox1) loci from a greatly expanded number of taxa to better assess generic relationships and understand patterns of character distributions. Our analyses produce the most well‐supported phylogeny of the family to date, and indicate that key characteristics of spermatangia and cystocarp type do not delineate genera as commonly suggested. Our results further indicate that Hydropuntia is not monophyletic. Given their morphological overlap with closely related members of Gracilaria, we propose that Hydropuntia be synonymized with the former. Our results additionally expand the known ranges of several Gracilariaceae species to include Brazil. Lastly, we demonstrate that the recently described Gracilaria yoneshigueana should be synonymized as G. domingensis based on morphological and molecular characters. These results demonstrate the utility of DNA barcoding for understanding poorly known and fragmentary materials of cryptic red algae.  相似文献   

6.
Alternaria fungi are important plant pathogens. Here, we identified three species new to the Japanese mycoflora: Alternaria celosiae, Alternaria crassa and Alternaria petroselini. We proposed a new name for A. celosiae (E.G. Simmons & Holcomb) Lawrence, Park & Pryor, a later homonym of A. celosiae (Tassi) O. S?vul. To characterize these and a fourth morphological taxon, Alternaria alstroemeriae, which was recently added to Japan's mycoflora, an integrated species concept was tested. We determined the host range of each isolate using inoculation tests and analysed its phylogenetic position using sequences of the internal transcribed spacer rDNA. The pathogenicity of our A. alstroemeriae isolate was strictly limited to Alstroemeria sp. (Alstroemeriaceae), but the species was phylogenetically indistinguishable from other small‐spored Alternaria. Alternaria celosiae on Celosia argentea var. plumosa (Amaranthaceae) was also pathogenic to Amaranthus tricolor, to Alternanthera paronychioides and weakly to Gomphrena globosa (all Amaranthaceae) and formed a clade with the former Nimbya celosiae. Alternaria crassa on Datura stramonium (Solanaceae) was also pathogenic to Brugmansia × candida and Capsicum annuum in Solanaceae, but not to other confamilial plants; phylogenetically it belonged to a clade of large‐spored species with filamentous beaks. Morphological similarity, phylogenetic relationship and experimental host range suggested that Acrassa, Alternaria capsici and Alternaria daturicola were conspecific. Alternaria petroselini on Petroselinum crispum (Apiaceae) was pathogenic to five species in the tribe Apieae as well as representatives of Bupleureae, Coriandreae, Seliaeae and Scandiceae in Apiaceae. Both phylogeny and morphology suggested conspecificity between Apetroselini and Alternaria selini.  相似文献   

7.
Scalopini is one of the two fully fossorial mole tribes in the family Talpidae, with remarkable adaptations to subterranean lifestyles. Most living Scalopini species are distributed in North America while a sole species occurs in China. On the other hand, scalopine fossils are found in both Eurasia and North America from upper Oligocene strata onwards, implying a complex biogeographical history. The systematic relationships of both extant and fossil Scalopini across North America and Eurasia are revised by conducting phylogenetic analyses using a comprehensive morphological character matrix together with 2D geometric–morphometric analyses of the humeral shape, with a specific emphasis on Mioscalops, a genus commonly found in North America and formerly known as Scalopoides. Our phylogenetic analyses support the monophyly of the tribe Scalopini as well as a proposed two‐subtribe‐division scenario of Scalopini (i.e. Scalopina and Parascalopina), although Proscapanus could not be assigned to either subgenus. Our geometric–morphometric analyses indicate that the European Mioscalops from southern Germany should be allocated to Leptoscaptor, which in turn implies that Mioscalops may be endemic to North America and never arrived in Europe. Examination of biogeographical patterns does not unambiguously determine the geographical origin of Scalopini. Nevertheless, it does support multiple transcontinental colonization events across Asia, Europe and North America. Scapanulus oweni, distributed in central China, is the only remaining representative of one of those out‐of‐North‐America migrations, whereas scalopine moles are common in North America nowadays with up to five species.  相似文献   

8.
The subfamily Crucigenioideae was traditionally classified within the well‐characterized family Scenedesmaceae (Chlorophyceae). Several morpho‐logical revisions and questionable taxonomic changes hampered the correct classification of crucigenoid species resulting in a high number of synonymous genera. We used a molecular approach to determine the phylogenetic position of several Tetrastrum and Crucigenia species. The molecular results were correlated with morphological and ontogenetic characters. Phylogenetic analyses of the SSU rDNA gene resolved the position of Tetrastrum heteracanthum and T. staurogeniaeforme as a new lineage within the Oocystis clade of the Trebouxiophyceae. Crucigenia tetrapedia, T. triangulare, T. punctatum, and T. komarekii were shown to be closely related to Botryococcus (Trebouxiophyceae) and were transferred to Lemmer‐mannia. Crucigenia lauterbornii was not closely related to the other Crucigenia strains, but was recovered within the Chlorella clade of the Trebouxiophyceae.  相似文献   

9.
Phylogenenetic relationships of the superfamily Tephritoidea (Diptera: Tephritidae) were reanalysed based upon four mitochondrial gene fragments (12S, 16S, cytochrome c oxidase I and cytochrome c oxidase II) from 53 tephritoid (10 families) and 30 outgroup (14 families) species. The data set of Han and Ro (Mol Phylogenet Evol, 39, 2005, 416) was expanded in terms of the number of taxa as well as molecular characters. We were able to sample the enigmatic families Ctenostylidae and Eurygnathomyiidae for the first time. Based on increased taxon sampling (from 49 to 83 species) and additional sequences (combined length of DNA fragments increased from 2451 to 4490 bp), the inferred phylogenetic trees suggest a number of interesting phylogenetic relationships, some of which were not recovered from the previous study. Some of the important findings are as follows: (1) monophyly of the superfamily Tephritoidea; (2) all the included tephritoid families except for Tephritidae were recovered as monophyletic groups; (3) Tephritoidea can be divided into two monophyletic groups – the Piophilidae Family Group (Pallopteridae, Circumphallidae?, Lonchaeidae, Piophilidae and Eurygnathomyiidae) and the Tephritidae Family Group (Richardiidae, Ulidiidae, Platystomatidae, Tephritidae, Ctenostylidae and Pyrgotidae); (4) Eurygnathomyiidae is recognized as an independent monophyletic family apart from Pallopteridae; (5) the enigmatic family Ctenostylidae is a member of the superfamily Tephritoidea; (6) parasitic Pyrgotidae + Ctenostylidae + Tachiniscinae and mostly phytophagous Tephritidae are recovered within a monophyletic group; and (7) according to an inferred chronogram, the first Tephritoidea might have evolved around the middle of Paleocene Epoch [~59 Million years ago (mya)] and the family Tephritidae around the late Eocene (~36 mya).  相似文献   

10.
The venomous snake subfamily Hydrophiinae includes more than 40 genera and approximately 200 species. Most members of this clade inhabit Australia, and have been well studied. But, because of poor taxon sampling of Melanesian taxa, basal evolutionary relationships have remained poorly resolved. The Melanesian genera Ogmodon, Loveridgelaps, and Salomonelaps have not been included in recent phylogenetic studies, and the New Guinean endemic, Toxicocalamus, has been poorly sampled and sometimes recovered as polyphyletic. We generated a multilocus phylogeny for the subfamily using three mitochondrial and four nuclear loci so as to investigate relationships among the basal hydrophiine genera and to determine the status of Toxicocalamus. We sequenced these loci for eight of the 12 described species within Toxicocalamus, representing the largest molecular data set for this genus. We found that a system of offshore island arcs in Melanesia was the centre of origin for terrestrial species of Hydrophiinae, and we recovered Toxicocalamus as monophyletic. Toxicocalamus demonstrates high genetic and morphological diversity, but some of the molecular diversity is not accompanied by diagnostic morphological change. We document at least five undescribed species that all key morphologically to Toxicocalamus loriae (Boulenger, 1898), rendering this species polyphyletic. Continued work on Toxicocalamus is needed to document the diversity of this genus, and is likely to result in the discovery of additional species. Our increased taxon sampling allowed us to better understand the evolution and biogeography of Hydrophiinae; however, several unsampled lineages remain, the later study of which may be used to test our biogeographic hypothesis.  相似文献   

11.
Specialist true predators are expected to exhibit higher capture efficiencies for the capture of larger and dangerous prey than generalist predators due to their possession of specialized morphological and behavioral adaptations. We used an araneophagous spider (Lampona murina) and a generalist spider (Drassodes lapidosus) as phylogenetically related model species and investigated their realized and fundamental trophic niches and their efficacy with respect to prey capture and prey handling. The trophic niche of both species confirmed that Lampona had a narrow trophic niche with a predominance of spider prey (including conspecifics), while the niche of Drassodes was wide, without any preference. DNA analysis of the gut contents of Lampona spiders collected in the field revealed that spiders form a significant part of its natural diet. Lampona captured significantly larger prey than itself and the prey captured by Drassodes. As concerns hunting strategy, Lampona grasped the prey with two pairs of legs possessing scopulae, whereas Drassodes immobilized prey with silk. Lampona possess forelegs equipped with scopulae and a thicker cuticle similar to other nonrelated araneophagous spiders. Lampona fed for a longer time and extracted more nutrients than Drassodes. We show that specialized behavioral and morphological adaptations altogether increase the hunting efficiency of specialists when compared to generalists.  相似文献   

12.
13.
The broadly defined genus Chaetophora consisted of species with minute, uniseriate branching filaments enveloped in soft or firm mucilage forming macroscopic growths that are spherical, hemispherical, and tubercular or arbuscular, growing epiphytically on freshwater aquatic plants and other submerged surfaces in standing or fast‐flowing water. Recent molecular analyses clearly showed that this genus was polyphyletic. In this study, eight strains of Chaetophora and three strains of Stigeoclonium were identified and successfully cultured. In combination with the morphological data, a concatenated data set of four markers (18S + 5.8S + ITS2+ partial 28S rDNA) was also used to determine their taxonomic relationships and phylogenetic positions. The molecular analysis resolved the broadly defined Chaetophora to at least two genera. Species with a globose thallus of genus Chaetophora formed a separate monophyletic clade, which clearly separated from, a type of lobe‐form Chaetophora species. Therefore, we propose to erect a new genus, Chaetophoropsis, which includes all globose species of the Chaetophora. Chaetophoropsis aershanensis was determined to be a new species, based on its special characteristic of profuse long rhizoids. Stigeoclonium polyrhizum, as the closest relative to Chaetophoropsis, revealed its distant relationships to other species of Stigeoclonium. A globose thallus with a thick, soft mucilage matrix, and special rhizoidal branches lent further support to the placement of S. polyrhizum in the genus Chaetophoropsis and had the closest relationship to C. aershanensis. Taxonomic diversity was proven by distinctive morphological differences and by phylogenetic divergence in the broadly defined Chaetophora identified herein.  相似文献   

14.
Chytrids are true fungi that reproduce with posteriorly uniflagellate zoospores. In the last decade, environmental DNA surveys revealed a large number of uncultured chytrids as well as undescribed order‐level novel clades in Chytridiomycota. Although many species have been morphologically described, only some DNA sequence data of parasitic chytrids are available from the database. We herein discuss five cultures of parasitic chytrids on diatoms Aulacoseira spp. and Asterionella formosa. In order to identify the chytrids examined, thallus morphologies were observed using light microscopy. We also conducted a phylogenetic analysis using 18S, 5.8S, and 28S rDNA sequences to obtain their phylogenetic positions. Based on their morphological characteristics, two cultures parasitic on As. formosa were identified as Rhizophydium planktonicum and Zygorhizidium planktonicum. The other three cultures infecting Aulacoseira spp. (two on Aulacoseira ambigua and the other on Aulacoseira granulata) were regarded as Zygorhizidium aff. melosirae. The results of the molecular phylogenetic analysis revealed that R. planktonicum belonged to the known order Chytridiales, while the two species of Zygorhizidium were placed in a novel clade that was previously reported as an undescribed clade composed of only the environmental sequences of uncultured chytrids.  相似文献   

15.
Phylogenetic relationships in Daltoniaceae (~200 species in 14 genera) are inferred from nucleotide sequences from five genes, representing all genomic compartments, using parsimony, likelihood and Bayesian methods. Alternative classifications for Daltoniaceae have favoured traits from either sporophytes or gametophytes; phylogenetic transitions in gametophytic leaf limbidia and sporophytic exostome ornamentation were evaluated using ancestral state reconstruction to assess the levels of conflict between these generations. Elimbate leaves and the cross‐striate exostome are reconstructed as plesiomorphic states. Limbate leaves and papillose exostomes evolved at least two and six times, respectively, without reversals. The evolution of leaf limbidia is relatively conserved, but exostome ornamentation is highly homoplasious, indicating that superficial similarity in peristomes gives unreliable approximations of phylogenetic relatedness. Our phylogenetic analyses show that Achrophyllum and Calyptrochaeta are reciprocally monophyletic. Within core Daltoniaceae, relationships among taxa with elimbate leaves are generally well understood. However, taxa with limbate leaves form a monophyletic group, but resolved subclades correspond to biogeographical entities, rather than to traditional concepts of genera. Daltonia (~21 species), Distichophyllum (~100 species) and Leskeodon (~20 species) are polyphyletic. Seven nomenclatural changes are proposed here. As the current taxonomy of Daltoniaceae lacks phylogenetic consistency, critical generic revisions are needed. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   

16.
Glassfishes of the family Ambassidae, comprising around 50 species, are distributed in the Indo‐West Pacific where they inhabit marine, estuarine, and freshwater ecosystems. We investigated for the first time the molecular phylogenetic and evolutionary relationships of this group using a combined dataset of mitochondrial and nuclear genes, particularly focusing on the taxa occurring in the Indian subcontinent. Results revealed that marine and freshwater genera of Ambassidae diverged during the Paleocene (~62 mya). The enigmatic monotypic genus Chanda is nested within the larger clade currently recognized as Parambassis, indicating its paraphyly. Based on cleared and stained osteological preparations and phylogenetic placement of Chanda nama, we hypothesize that the elongated and protruding lower jaw is an autapomorphic character that might have evolved for the lepidophagous habit of the species. The southern Indian species of Parambassis, Parambassis dayi, and Parambassis thomassi, which formed a monophyletic group, probably diverged from other species of Parambassis and Chanda nama around the Eocene (~42 mya) and can potentially be recognized as a distinct genus in view of the apomorphic characters such as the presence of serration on the ventral fringe of interopercle, densely serrated palatine and ectopterygoid, and the presence of more than 30 serrations along the lower preopercle and the posterior edge. Our analysis provides new insights into the evolution and phylogenetic relationships of glassy perchlets, including detailed relationships among the Indian species within this family.  相似文献   

17.
Photosynthetic euglenids acquired chloroplasts by secondary endosymbiosis, which resulted in changes to their mode of nutrition and affected the evolution of their morphological characters. Mapping morphological characters onto a reliable molecular tree could elucidate major trends of those changes. We analyzed nucleotide sequence data from regions of three nuclear‐encoded genes (nSSU, nLSU, hsp90), one chloroplast‐encoded gene (cpSSU) and one nuclear‐encoded chloroplast gene (psbO) to estimate phylogenetic relationships among 59 photosynthetic euglenid species. Our results were consistent with previous works; most genera were monophyletic, except for the polyphyletic genus Euglena, and the paraphyletic genus Phacus. We also analyzed character evolution in photosynthetic euglenids using our phylogenetic tree and eight morphological traits commonly used for generic and species diagnoses, including: characters corresponding to well‐defined clades, apomorphies like presence of lorica and mucilaginous stalks, and homoplastic characters like rigid cells and presence of large paramylon grains. This research indicated that pyrenoids were lost twice during the evolution of phototrophic euglenids, and that mucocysts, which only occur in the genus Euglena, evolved independently at least twice. In contrast, the evolution of cell shape and chloroplast morphology was difficult to elucidate, and could not be unambiguously reconstructed in our analyses.  相似文献   

18.
19.
Gregarines are a diverse group of apicomplexan parasites with a conspicuous extracellular feeding stage, called a “trophozoite”, that infects the intestines and other body cavities of invertebrate hosts. Although the morphology of trophozoites is very diverse in gregarines as a whole, high degrees of intraspecific variation combined with relatively low degrees of interspecific variation make the delimitation of different species based on trophozoite morphology observed with light microscopy difficult. The coupling of molecular phylogenetic data with comparative morphology has shed considerable light onto the boundaries and interrelationships of different gregarine species. In this study, we isolated a novel marine gregarine from the hepatic region of a Pacific representative of the hemichordate Glossobalanus minutus, and report the first ultrastructural and molecular data from any gregarine infecting this distinctive group of hosts. Molecular phylogenetic analyses of an SSU rDNA sequence derived from two single‐cell isolates of this marine gregarine demonstrated a strong and unexpected affiliation with a clade of terrestrial gregarines (e.g. Gregarina). This molecular phylogenetic data combined with a comparison of the morphological features in previous reports of gregarines collected from Atlantic representatives of G. minutus justified the establishment of a new binomial for the new isolate, namely Caliculium glossobalani n. gen. et sp. The molecular phylogenetic analyses demonstrated a clade of terrestrial gregarines associated with a sequence acquired from a marine species, which suggest that different groups of terrestrial/freshwater gregarines evolved independently from marine ancestors.  相似文献   

20.
Transferred copies of mitochondrial DNA (mtDNA) into the nuclear genome (numts) have been reported in several Hymenoptera species, even at a high density in the honey bee nuclear genome. The accidental amplification of numts in phylogenetic studies focused on mtDNA highlights the importance of a correct determination of numts and their related mtDNA sequences. We report here the presence of numts derived from a mitochondrial rDNA 16S gene in the genome of the stingless bee species Melipona colimana and M. fasciata (tribe Meliponini) from Western Mexico. PCR products were cloned in both species obtaining thirty paralogous numts. Numts were identified by the presence of insertions and deletions and the disruption of the 16S secondary structure. Further phylogenetic analyses including alternative mitochondrial cox1 and nuclear ITS1 genes have revealed the presence of another numt (cox1) in the nuclear genome of these two species, and place both as sister lineages within the subgenus Michmelia. This is one of the first studies reporting the presence of numts in Meliponini species, and supports previous studies suggesting frequent transfer of mtDNA to the nuclear genome in Hymenoptera.  相似文献   

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