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1.
The Labeonini (sensu Rainboth, 1991) is a tribe of the subfamily Cyprininae, the largest subfamily of Cypriniformes. With around 400 species in 34 genera, this tribe is widely distributed in the freshwaters of tropical Africa and Asia. Most species are adapted to fast-flowing streams and rivers, and exhibit unique morphological modifications associated with their lips and other structures around the mouth. The monophyly of this tribe has been tested and generally accepted in previous morphological and molecular studies. The major objectives of this study were to reconstruct the phylogenetic relationships within the tribe Labeonini, test its monophyly and explore the taxonomic subdivisions, intrarelationships and biogeography of the group. The value of the morphological characters associated with the lips and other associated structures in the taxonomic classification of labeonins was also discussed. Nucleotide sequences (3867 bp) of four unlinked nuclear loci were obtained from 51 species in 18 Labeonini genera from throughout the range of the tribe. Maximum parsimony, partitioned maximum likelihood and partitioned Bayesian analyses were used for phylogenetic inference from combined and separate gene data sets. Based on our results, the monophyly of Labeonini was well supported. Two major clades could be recovered within the tribe. Three subclades could further be recognized from the first clade. These clades/subclades are not consistent with groupings of any of previous workers using either morphological or molecular characters for phylogenetic inference. Only five currently recognized genera in this analysis are monophyletic. The similarity between some lips and associated structures (e.g. suctorial discs) of labeonins may due to convergence or parallelism instead of common ancestry. Labeonins of Southeast Asia, India and China are closely related to each other; the multiple clades of African taxa do not form a single monophyletic group, indicating multiple, independent dispersal events of labeonins into Africa from Asia.  相似文献   

2.
A wide range of transitional forms of granular interstitia from simple to complex and from random to ordered occur in the pollen of the subfamily Papilionoideae. Three main types are described: 1) large, widely spaced irregular granules (Type A); 2) densely packed groups of columellae and granules (Type B); and 3) a mass of more or less disorganized granules (Type C). In the genus Calopogonium (tribe Phaseoleae) all three types have been found in different species. Two of the types have been found in different species of the genus Psoralea (tribe Psoraleeae). Granular structures so far occur in six tribes: Desmodieae, Indigofereae, Loteae, Phaseoleae, Psoraleeae, and Vicieae. All of the tribes are regarded as being evolutionarily advanced in both macro and micro characters and many, but not all, show specialized pollen characters. It is concluded that the granular interstitium is a derived structure in papilionoid legumes.  相似文献   

3.
The tribe Pogonieae of Vanilloideae (Orchidaceae) consists of six genera, including Pogoniopsis, a myco-heterotrophic taxon with morphological characteristics distinct from the remaining of the tribe. A hypothesis about the phylogeny of the tribe was inferred, involving all currently recognized genera, based on isolated and combined sequence data of 5.8S, 18S and 26S (nrDNA) regions using parsimony and Bayesian analyses. Phylogenetic analyses show that inclusion of Pogoniopsis turns the tribe Pogonieae paraphyletic. All analyses reveal that Pogoniopsis is closely related to members of Epidendroideae. The pantropical Vanilla is monophyletic if Dictyophyllaria is assumed as synonym of Vanilla. Members of Pogonieae are pollinated by several groups of solitary and social bees, two pollination systems being recognized: reward-producing and deceptive. The molecular phylogeny suggests that ancestrals related to Pogonieae gave rise to two evolutionary lines: a tropical one with reward production of flowers, and a predominantly temperate regions invading line with deceptive flowers. Reward-producing flowers characterize the South and Central American clade (=Cleistes), while deceptive pollination is prominent in the clade that includes North American-Asiatic taxa plus the Amazonian genus Duckeella.  相似文献   

4.
Generic boundaries among the genera Cheilosporum, Haliptilon, and Jania—currently referred to the tribe Janieae (Corallinaceae, Corallinales, Rhodophyta)—were reassessed. Phylogenetic relationships among 42 corallinoidean taxa were determined based on 26 anatomical characters and nuclear SSU rDNA sequence data for 11 species (with two duplicate plants) referred to the tribe Corallineae and 15 species referred to the tribe Janieae (two species of Cheilosporum, seven of Haliptilon, and six of Jania, with five duplicate plants). Results from our approach were consistent with the hypothesis that the tribe Janieae is monophyletic. Our data indicate, however, that Jania and Haliptilon as currently delimited are not monophyletic, and that Cheilosporum should not be recognized as an independent genus within the Janieae. Our data resolved two well‐supported biogeographic clades for the included Janieae, an Indian‐Pacific clade and a temperate North Atlantic clade. Among anatomical characters, reproductive structures reflected the evolution of the Janieae. Based on our results, three genera, Cheilosporum, Haliptilon, and Jania, should be merged into a single genus, with Jania having nomenclatural priority. We therefore propose new combinations where necessary of some species previously included in Cheilosporum and Haliptilon.  相似文献   

5.
Seventy-nine species representing 12 genera of Vitaceae were sequenced for the trnL-F spacer, 37 of which were subsequently sequenced for the atpB-rbcL spacer and the rps16 intron. Phylogenetic analysis of the combined data provided a fairly robust phylogeny for Vitaceae. Cayratia, Tetrastigma, and Cyphostemma form a clade. Cyphostemma and Tetrastigma are each monophyletic, and Cayratia may be paraphyletic. Ampelopsis is paraphyletic with the African Rhoicissus and the South American Cissus striata nested within it. The pinnately leaved Ampelopsis form a subclade, and the simple and palmately leaved Ameplopsis constitutes another with both subclades containing Asian and American species. Species of Cissus from Asia and Central America are monophyletic, but the South American C. striata does not group with other Cissus species. The Asian endemic Nothocissus and Pterisanthes form a clade with Asian Ampelocissus, and A. javalensis from Central America is sister to this clade. Vitis is monophyletic and forms a larger clade with Ampelocissus, Pterisanthes, and Nothocissus. The eastern Asian and North American disjunct Parthenocissus forms a clade with Yua austro-orientalis, a species of a small newly recognized genus from China to eastern Himalaya. Vitaceae show complex multiple intercontinental relationships within the northern hemisphere and between northern and southern hemispheres.  相似文献   

6.
Helopini is a diverse tribe in the subfamily Tenebrioninae with a worldwide distribution. The New World helopine species have not been reviewed recently and several doubts emerge regarding their generic assignment as well as the naturalness of the tribe and subordinate taxa. To assess these questions, a preliminary cladistic analysis was conducted with emphasis on sampling the genera distributed in the New World, but including representatives from other regions. The parsimony analysis includes 30 ingroup species from America, Europe and Asia of the subtribes Helopina and Cylindrinotina, plus three outgroups, and 67 morphological characters. Construction of the matrix resulted in the discovery of morphological character states not previously reported for the tribe, particularly from the genitalia of New World species. A consensus of the 12 most parsimonious trees supports the monophyly of the tribe based on a unique combination of characters, including one synapomorphy. None of the subtribes or the genera of the New World represented by more than one species (Helops Fabricius, Nautes Pascoe and Tarpela Bates) were recovered as monophyletic. Helopina was recovered as paraphyletic in relation to Cylindrinotina. One Nearctic species of Helops and one Palearctic species of Tarpela (subtribe Helopina) were more closely related to species of Cylindrinotina. A relatively derived clade, mainly composed by Neotropical species, was found; it includes seven species of Tarpela, seven species of Nautes, and three species of Helops, two Nearctic and one Neotropical. Our results reveal the need to deeply re-evaluate the current classification of the tribe and subordinated taxa, but a broader taxon sampling and further character exploration is needed in order to fully recognize monophyletic groups at different taxonomic levels (from subtribes to genera).  相似文献   

7.
Cladistic analyses of plastid DNA sequences rbcL and trnL-F are presented separately and combined for 48 genera of Amaryllidaceae and 29 genera of related asparagalean families. The combined analysis is the most highly resolved of the three and provides good support for the monophyly of Amaryllidaceae and indicates Agapanthaceae as its sister family. Alliaceae are in turn sister to the Amaryllidaceae/Agapanthaceae clade. The origins of the family appear to be western Gondwanaland (Africa), and infrafamilial relationships are resolved along biogeographic lines. Tribe Amaryllideae, primarily South African, is sister to the rest of Amaryllidaceae; this tribe is supported by numerous morphological synapomorphies as well. The remaining two African tribes of the family, Haemantheae and Cyrtantheae, are well supported, but their position relative to the Australasian Calostemmateae and a large clade comprising the Eurasian and American genera, is not yet clear. The Eurasian and American elements of the family are each monophyletic sister clades. Internal resolution of the Eurasian clade only partially supports currently accepted tribal concepts, and few conclusions can be drawn on the relationships of the genera based on these data. A monophyletic Lycorideae (Central and East Asian) is weakly supported. Galanthus and Leucojum (Galantheae pro parte) are supported as sister genera by the bootstrap. The American clade shows a higher degree of internal resolution. Hippeastreae (minus Griffinia and Worsleya) are well supported, and Zephyranthinae are resolved as a distinct subtribe. An Andean clade marked by a chromosome number of 2n = 46 (and derivatives thereof) is resolved with weak support. The plastid DNA phylogenies are discussed in the context of biogeography and character evolution in the family.  相似文献   

8.
9.
Legume subfamily Caesalpinioideae accommodates approximately 2250 species in 171 genera which traditionally are placed in four tribes: Caesalpinieae, Cassieae, Cercideae and Detarieae. The monophyletic tribe Detarieae includes the Amherstieae subclade which contains about 55 genera. Our knowledge of the relationships among those genera is good in some cases but for many other genera phylogenetic relationships have been unclear. The non-monophyletic nature of at least two amherstioid genera, Cynometra and Hymenostegia has also complicated the picture. During the course of a multi-disciplinary study of Hymenostegia sensu lato, which includes phylogenetic analyses based on matK and trnL data, we have recovered the “Scorodophloeus clade”, an exclusively tropical African clade of four genera which includes the eponymous genus Scorodophloeus, two undescribed generic segregates of Hymenostegia sensu lato, and the previously unsampled rare monospecific genus Micklethwaitia from Mozambique. Zenkerella is suggested as a possible sister genus to the Scorodophloeus clade. A distribution map is presented of the seven species that belong to the Scorodophloeus clade.  相似文献   

10.
The tribe Acraeini (Nymphalidae, Heliconiinae) is believed to comprise between one and seven genera, with the greatest diversity in Africa. The genera Abananote, Altinote, and Actinote (s. str.) are distributed in the Neotropics, while the genera Acraea, Bematistes, Miyana, and Pardopsis have a Palaeotropical distribution. The monotypic Pardopsis use herbaceous plants of the family Violaceae, Acraea and Bematistes feed selectively on plants with cyanoglycosides belonging to many plant families, but preferentially to Passifloraceae, and all Neotropical species with a known life cycle feed on Asteraceae only. Here, a molecular phylogeny is proposed for the butterflies of the tribe Acraeini based on sequences of COI, EF-1alpha and wgl. Both Maximum Parsimony and Bayesian analyses showed that the tribe is monophyletic, once the genus Pardopsis is excluded, since it appears to be related to Argynnini. The existing genus Acraea is a paraphyletic group with regard to the South American genera, and the species of Acraea belonging to the group of "Old World Actinote" is the sister group of the Neotropical genera. The monophyly of South American clade is strongly supported, suggesting a single colonization event of South America. The New World Actinote (s. str.) is monophyletic, and sister to Abananote+Altinote (polyphyletic). Based on the present results it was possible to propose a scenario for the evolution in host plant use within Acraeini, mainly concerning the use of Asteraceae by the South American genera.  相似文献   

11.
Using sequences from the plastid trnL-F region and nrDNA ITS, we investigated the phylogeny of the fleshy-fruited African tribe Haemantheae of the Amaryllidaceae across 19 species representing all genera of the tribe. ITS and a combined matrix produce the most resolute and well-supported tree with parsimony analysis. Two main clades are resolved, one comprising the monophyletic rhizomatous genera Clivia and Cryptostephanus, and a larger clade that unites Haemanthus and Scadoxus as sister genera to an Apodolirion/Gethyllis subclade. One of four included Gethyllis species, G. lanuginosa, resolves as sister to Apodolirion with ITS. Relationships among the Clivia species are not in agreement with a previous published phylogeny. Biogeographic analysis using the divergence/vicariance method roots the tribe in Eastern South Africa, with several subsequent dispersals to the winter rainfall Western Cape region. Chromosomal change from an ancestral 2n=22 (characteristic of Clivia) is associated with each main clade. Reduction in number has occurred in all but Cryptostephanus, which has 2n=24 chromosomes. Increasing the sampling across all of the species in the tribe will allow a more detailed understanding of the biogeographic patterns inherent in the parsimony topology, which undoubtedly reflect Quaternary climatic changes in Southern Africa.  相似文献   

12.
13.
The Menispermaceae family contains ca. 72 genera with 450 species that are almost entirely tropical. Its phylogeny at the tribal level has never been examined using molecular data. Here we used DNA sequences of the chloroplast matK gene and trnL-F regions, and the nuclear ITS region to study the delimitation and position of the tribe Menispermeae within the family and its subtribal monophyletic groups. Family-wide phylogenetic analyses of the chloroplast data produced two strongly supported clades. The first clade contains two subclades: Coscinieae including Arcangelisia and Anamirta, and Tinosporeae sensu lato including Fibraureae, supported by morphological characters, such as traits of the cotyledon, stylar scar and embryo. The second clade consists of the tribes Menispermeae sensu DC. and Tiliacoreae Miers. All our analyses surprisingly recognized that tribe Menispermeae is not monophyletic unless tribe Tiliacoreae is included, suggesting that characters of cotyledon and stylar scar are very important for the infrafamilial classification, and that endosperm presence vs. absence was over-emphasized in traditionally tribal division of the family. Our topologies indicate a secondary loss of endosperm. The monophyly of two subtribes of the tribe Menispermeae, Stephaniinae and Cissampelinae, is supported by the cpDNA and ITS data, as well as by morphological characters, including aperture types and shapes, and colpal membrane features of pollen grains, and sepal number of male flowers. The Cocculinae was recognized as a paraphyletic group containing the remaining genera of the tribe Menispermeae.  相似文献   

14.
The tribe Abrotrichini (five genera and 14 living species) is a small clade within the speciose subfamily Sigmodontinae (Rodentia, Cricetidae), representing one of the extant successful radiations of mammals at southern high latitudes of the Neotropics. Its distribution is mostly Andean, reaching its greatest diversity in southern Argentina and Chile. We evaluate the phylogenetic relationships within this tribe through parsimony and Bayesian approaches based on 99 morphological characters (including 19 integumental characters, 38 skull characters, 31 dental characters, three postcranial skeletal characters, seven from the male accessory glands and phallus and one from the digestive system) and six molecular markers (one mitochondrial and five nuclear). We include representatives of all, except one, of the currently recognized species of living Abrotrichini plus one fossil form. Based on total evidence, we recovered a primary division between the genus Abrothrix and a group including the long‐clawed Abrotrichini, Chelemys, Geoxus, Notiomys and Pearsonomys. Both clades are recognized and named here as subtribes. The large degree of morphological variation observed within Abrothrix suggests that species in the genus fall into four groups, which we recognize as subgenera. In addition, the two known species of Chelemys do not form a monophyletic group, and Geoxus was recovered as paraphyletic with respect to Pearsonomys. To reconcile classification and phylogenetics, we describe a new genus for Chelemys macronyx and include Pearsonomys as a junior synonym of Geoxus. Our results highlight the importance of both morphology and molecules in resolving the phylogenetic relationships within this tribe. Based on biogeographical analyses, we hypothesize that Abrotrichini originated in south‐western South America by vicariance and then diversified mostly by successive dispersal events.  相似文献   

15.
A phylogenetic analysis based on 58 morphological characters including 18 species representing 14 genera over the 15 currently known in Darnini (Hemiptera: Membracidae) confirms the monophyly of this tribe. This result is particularly supported by the presence of cucullate setae on the ventral side of the femora. Two sister clades are inferred: the clade Funkhouseriana+ which groups four genera (Aspona, Cyphotes, Funkhouseriana, Taunaya) and exhibits a ‘bird dropping’ habitus and all other genera which exhibit a ‘dewdrop’ like habitus (Alobia, Darnis, Dectonura, Hebetica, Hebeticoides, Leptosticta, Ochrolomia, Stictopelta) or a ‘thorny’ habitus (Alcmeone, Sundarion). In the ‘dewdrop’ habitus, only the clade Ochrolomia+ is retained as a monophyletic unit. According to these results, pronotal shapes and habitus have evolved independently in each monophyletic unit and each one seems correlated with a particular type of mimicry strategy. According to the strategy, characters involved are different, a priori independent; moreover, they look coordinated regarding to the mimicry function they serve. The various evolutionary scenarios are discussed in relation to the phylogeny, and particularly in correlation with the non-gregarious behavior of these membracids, also coherent with their mimicry strategy.  相似文献   

16.
Molecular phylogenies often reveal that taxa circumscribed by phenotypical characters are not monophyletic. While re-examination of phenotypical characters often identifies the presence of characters characterizing clades, there is a growing number of studies that fail to identify diagnostic characters, especially in organismal groups lacking complex morphologies. Taxonomists then can either merge the groups or split taxa into smaller entities. Due to the nature of binomial nomenclature, this decision is of special importance at the generic level. Here we propose a new approach to choose among classification alternatives using a combination of morphology-based phylogenetic binning and a multiresponse permutation procedure to test for morphological differences among clades. We illustrate the use of this method in the tribe Thelotremateae focusing on the genus Chapsa, a group of lichenized fungi in which our phylogenetic estimate is in conflict with traditional classification and the morphological and chemical characters do not show a clear phylogenetic pattern. We generated 75 new DNA sequences of mitochondrial SSU rDNA, nuclear LSU rDNA and the protein-coding RPB2. This data set was used to infer phylogenetic estimates using maximum likelihood and Bayesian approaches. The genus Chapsa was found to be polyphyletic, forming four well-supported clades, three of which clustering into one unsupported clade, and the other, supported clade forming two supported subclades. While these clades cannot be readily separated morphologically, the combined binning/multiresponse permutation procedure showed that accepting the four clades as different genera each reflects the phenotypical pattern significantly better than accepting two genera (or five genera if splitting the first clade). Another species within the Thelotremateae, Thelotrema petractoides, a unique taxon with carbonized excipulum resembling Schizotrema, was shown to fall outside Thelotrema. Consequently, the new genera Astrochapsa, Crutarndina, Pseudochapsa, and Pseudotopeliopsis are described here and 39 new combinations are proposed.  相似文献   

17.
Cinereomyces clade is a newly proposed monophyletic group of polypores containing currently four genera and five species, including two promising biopulping fungi, Ceriporiopsis rivulosa and C. subvermispora. The Cinereomyces clade is well-delimited in nrDNA-based phylogenetic analysis, but its position in Polyporales remains unclear. Its closest relative may be found in the core polyporoid clade. Only a few morphological characters are common for all the species in the clade, e.g. CB– and CRB+ hyphae, white fruiting bodies, presence of oil, and middle-sized spores. Culturally, the species are unified by producing simple-septate generative hyhpae in the margin, which produce simple-clamped hyphae backwards. The genus Gelatoporia is the correct place for Ceriporiopsis subvermispora. Two new genera are described in the group: Obba to incorporate C. rivulosa and a new austral species, Obba valdiviana, known from southern Argentina and recorded here also from Tasmania, and Sebipora to accommodate a new species from tropical Asia, S. aquosa. ITS sequences imply that Eurasian Gelatoporia subvermispora may belong to a different species from the North American one. G. subvermispora is recorded as new to Indonesia.  相似文献   

18.
The tribe Acacieae (Fabaceae: Mimosoideae) contains two genera, the monotypic African Faidherbia and the pantropical Acacia, which comprise about 1200 species with over 950 confined to Australia. As currently recognized, the genus Acacia is subdivided into three subgenera: subg. Acacia, subg. Aculeiferum, and the predominantly Australian subg. Phyllodineae. Morphological studies have suggested the tribe Acacieae and genus Acacia are artificial and have a close affinity to the tribe Ingeae. Based on available data there is no consensus on whether Acacia should be subdivided. Sequence analysis of the chloroplast trnK intron, including the matK coding region and flanking noncoding regions, indicate that neither the tribe Acacieae nor the genus Acacia are monophyletic. Two subgenera are monophyletic; section Filicinae of subgenus Aculeiferum does not group with taxa of the subgenus. Section Filicinae, eight Ingeae genera, and Faidherbia form a weakly supported paraphyletic grade with respect to subg. Phyllodineae. Acacia subg. Aculeiferum (s. s.) is sister to the grade. These data suggest that characters currently used to differentiate taxa at the tribal, generic, and subgeneric levels are polymorphic and homoplasious in cladistic analyses.  相似文献   

19.
20.
A cladistic analysis based on 63 morphological characters was carried out on the tribe Colletieae including two presumed closely related genera, Geanothus and Noltea as outgroupS. In addition to a parsimony analysis of the equally weighted characters, analyses investigating the effects of character weighting, removal of a presumed hybrid species as well as the impact of uncertainly scored characters were undertaken. In all analyses Noltea was placed as sister group to a well supported monophyletic Colletieae. Nineteen different in group topologies were found, with the additional analyses mainly supporting two of them. Within the Colletieae a basal dichotomy divides Trevoa and Retanilla from the remainder of the tribe. While the Trevoa-Retanilla clade is fully resolved, the second lacks detailed resolution. Within this clade the Colletia species from a well supported monophyletic group, while monophyly of the disjunct genus Discaria could not be confirmed.  相似文献   

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