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1.
The marmosets, tribe Callitrichini, are the most speciose clade in the subfamily Callitrichinae, containing 21 species. However, there is no consensus among molecular and morphological systematists as to how many genera should be recognized for the group. To test the morphological support for the alternative generic classifications, this study presents a comprehensive phylogenetic analysis. It is the first such analysis to include all 21 species and employ continuous and discrete osteological, pelage and tegument, karyological and vocal characters. This dataset was combined with nucleotide sequences from two mitochondrial and four nuclear regions. Separate analyses showed that, among morphological datasets, osteological characters were best at solving relationships at more inclusive levels, whilst pelage characters were most informative at the interspecific level. This suggests the presence of different transformation rates for the two character sets. When a single most parsimonious tree was obtained using the 83‐character matrix, three main clades were identified, supporting the division of the marmosets into three genera: Callithrix, Cebuella and Mico. The total evidence analysis that included an additional 3481 molecular characters corroborated most of the morphology‐based clades and also supported a three‐genus classification of the marmosets. This is the first morphological study to support an Amazonian marmoset clade (Cebuella Mico), which is also strongly supported in exclusively molecular phylogenies, and to synonimize Callibella under Mico.  相似文献   

2.
The phylogenetic position of Cetacea (whales, dolphins and porpoises) is an important exemplar problem for combined data parsimony analyses because the clade is ancient and includes many well‐known and relatively complete fossil species. We combined data for 71 terminal taxa (43 extinct/28 extant) to test where Cetacea fits within Cetartiodactyla, and where various fossil hoofed mammals (e.g., ?entelodonts, “?anthracotheriids” and ?mesonychians) are positioned. We scored 635 phenotypic characters (osteology, dentition, soft tissue, behavior), approximately three times the number of characters in the last major analysis of this clade, and combined these with > 40 000 molecular characters, including new data from 10 genes. The analysis supported a topology consistent with the majority of recently published molecular studies. Cetacea was the extant sister taxon of Hippopotamidae, followed successively by Ruminantia, Suina and Camelidae. Several extinct taxa were phylogenetically unstable, upsetting resolution of the strict consensus and limiting branch support, but the positions of several key fossils were consistently resolved. The wholly extinct ?Mesonychia was more closely related to Cetacea than was any “artiodactylan.”“?Anthracotheriids” were paraphyletic, and, with the exception of one species, were more closely related to Hippopotamidae than to any other living taxon. The total evidence analysis overturned a highly nested position for Moschus supported by molecular data alone. The character partition that could be scored for the fossil taxa (osteological and dental characters) included more informative characters than most molecular partitions in our analysis, and had the fewest missing data. The osteological–dental data alone, however, did not support inclusion of cetaceans within crown “Artiodactyla.” Recently discovered ankle bones from fossil whales reinforced the monophyly of Cetartiodactyla but provided no particular evidence of derived similarities between hippopotamids and fossil cetaceans that were not shared with other “artiodactylans”. © The Willi Hennig Society 2007.  相似文献   

3.
The phylogenetic relationships of the five living species of umbrids are examined through a comparative osteological study based on a series of cleared-and-stained specimens of each species. The Umbridae appear to be strictly monophyletic. In addition, for 45 characters, the outgroup Esox shares one character-state with at least one umbrid species, while two or more umbrid species share the other state. Assuming that the states shared with Esox are primitive for the Umbridae, the hypothesis that Dallia is more closely related to Umbra than to Novumbra is supported by compatibility and Wagner-tree analysis of the data. Thirteen derived characters are shared by Dallia and Umbra , 20 more are shared by the three species of Umbra , and four more by U. limi and U. pygmaea. Eight characters are considered likely to have undergone reversal or parallel evolution.  相似文献   

4.
5.
We performed the first combined‐data phylogenetic analysis of ictalurids including most living and fossil species. We sampled 56 extant species and 16 fossil species representing outgroups, the seven living genera, and the extinct genus ?Astephus long thought to be an ictalurid. In total, 209 morphological characters were curated and illustrated in MorphoBank from published and original work, and standardized using reductive coding. Molecular sequences harvested from GenBank for one nuclear and four mitochondrial genes were combined with the morphological data for total evidence analysis. Parsimony analysis recovers a crown clade Ictaluridae composed of seven living genera and numerous extinct species. The oldest ictalurid fossils are the Late Eocene members of Ameiurus and Ictalurus. The fossil clade ?Astephus placed outside of Ictaluridae and not as its sister taxon. Previous morphological phylogenetic studies of Ictaluridae hypothesized convergent evolution of troglobitic features among the subterranean species. In contrast, we found morphological evidence to support a single clade of the four troglobitic species, the sister taxon of all ictalurids. This result holds whether fossils are included or not. Some previously published clock‐based age estimates closely approximate our minimum ages of clades.  相似文献   

6.
Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Caribbean. We estimated phylogenetic relationships among sphaerodactyl genera using both separate and combined analyses of seven nuclear genes. Relationships among genera were incongruent at different loci and phylogenies were characterized by short, in some cases zero length, internal branches and poor phylogenetic support at most nodes. We recovered a polyphyletic Coleodactylus, with Coleodactylus amazonicus being deeply divergent from the remaining Coleodactylus species sampled. The C. amazonicus lineage possessed unique codon deletions in the genes PTPN12 and RBMX while the remaining Coleodactylus species had unique codon deletions in RAG1. Topology tests could not reject a monophyletic Coleodactylus, but we show that short internal branch lengths decreased the accuracy of topology tests because there were not enough data along short branches to support one phylogenetic hypothesis over another. Morphological data corroborated results of the molecular phylogeny, with Coleodactylus exhibiting substantial morphological heterogeneity. We identified a suite of unique craniofacial features that differentiate C. amazonicus not only from other Coleodactylus species, but also from all other geckos. We describe this novel sphaerodactyl lineage as a new genus, Chatogekko gen. nov. We present a detailed osteology of Chatogekko, characterizing osteological correlates of miniaturization that provide a framework for future studies in sphaerodactyl systematics and biology.  相似文献   

7.
Among the 13 genera and over 100 species of halfbeaks, three genera - Dermogenys, Nomorhamphus and Hemirhamphodon – are internally fertilized and viviparous. These genera belong to a more inclusive clade, the Zenarchopterinae, that also includes Zenarchopterus , inferred to be internally fertilized and to lay fertilized eggs, and the monotypic Tondanichthys , also inferred to be internally fertilized. Whereas the Hemiramphidae are distributed worldwide, internally fertilized halfbeaks are restricted to Southeast Asia. Recent data from histological surveys of the gonads of both males and females as well as embryonic modifications associated with viviparity have been combined here with osteological characters in a phylogenetic analysis. Results indicate overwhelming support for a sister-group relationship between Hemirhamphodon and {Dermogenys + Nomorhamphus). Monophyly of the Dermogenys + Nomorhamphus clade is also well supported. These results confirm earlier suggestions that Dermogenys , as previously defined, is paraphyletic. Within the Dermogenys + Nomorhamphus clade, two monophyletic clades are supported:one comprises ten species including four new species (Dermogenys bruneiensis, Dermogenys robertsi, Dermogenys palawanensis and Dermogenys collettei) and the other comprises 13 species including three undescribed species (Nomorhamphus rossi, Nomorhamphus pinnimaculata and Nomorhamphus manifesta). Diagnoses for the species of Dermogenys and Nomorhamphus , as well as a natural classification for the included species, are presented.  相似文献   

8.
A phylogeny of sparoid fishes (Perciformes, Percoidei) based on morphology   总被引:2,自引:0,他引:2  
 The putative percoid superfamily Sparoidea includes the Nemipteridae, Lethrinidae, Sparidae, and Centracanthidae. Although a rigorous cladistic analysis has never been attempted, two hypotheses regarding relationships among these families have been proposed. One early noncladistic hypothesis considered the Sparidae to be intermediate between the more primitive Nemipteridae and the more derived Lethrinidae. A later nonformal phylogenetic treatment provided evidence for a close relationship between Sparidae and Centranthidae and suggested a closer affinity between the Nemipteridae and Lethrinidae. We examine 54 osteological, ligament, and squamation characters in representatives of all 45 genera of these families and 4 outgroup taxa. The results of our cladistic analysis are congruent with a cladistic interpretation of the earlier hypothesis, with strong support for the phyletic sequence Nemipteridae, Lethrinidae, Sparidae plus Centracanthidae, with placement of centracanthids unresolved with respect to sparid genera. Received: May 21, 2001 / Revised: October 26, 2001 / Accepted: November 19, 2001  相似文献   

9.
10.
Given that most species that have ever existed on Earth are extinct, no evolutionary history can ever be complete without the inclusion of fossil taxa. Bovids (antelopes and relatives) are one of the most diverse clades of large mammals alive today, with over a hundred living species and hundreds of documented fossil species. With the advent of molecular phylogenetics, major advances have been made in the phylogeny of this clade; however, there has been little attempt to integrate the fossil record into the developing phylogenetic picture. We here describe a new large fossil caprin species from ca. 1.9-Ma deposits from the Middle Awash, Ethiopia. To place the new species phylogenetically, we perform a Bayesian analysis of a combined molecular (cytochrome b) and morphological (osteological) character supermatrix. We include all living species of Caprini, the new fossil species, a fossil takin from the Pliocene of Ethiopia (Budorcas churcheri), and the insular subfossil Myotragus balearicus. The combined analysis demonstrates successful incorporation of both living and fossil species within a single phylogeny based on both molecular and morphological evidence. Analysis of the combined supermatrix produces superior resolution than with either the molecular or morphological data sets considered alone. Parsimony and Bayesian analyses of the data set are also compared and shown to produce similar results. The combined phylogenetic analysis indicates that the new fossil species is nested within Capra, making it one of the earliest representatives of this clade, with implications for molecular clock calibration. Geographical optimization indicates no less than four independent dispersals into Africa by caprins since the Pliocene.  相似文献   

11.
The Cracidae are Neotropical galliform birds with 11 genera currently recognized. To investigate the questioned validity of Pipile Bonaparte, 1856 and the monotypic Aburria Reichenbach, 1853 as separate genera, we gathered data from 2727 bp of mitochondrial DNA (cytochrome b, ND2 and control region) and 151 osteological characters. Our phylogenetic analyses of DNA sequences indicated that Aburria aburri is embedded within Pipile. Also, genetic distances between Aburria and any Pipile species are equivalent to the distances estimated for other congeneric cracid species, which genus status is not doubtful. Although the osteological characters do not have phylogenetic signal to solve the phylogenetic relationships at species level, five synapomorphies were found for Aburria and Pipile. Therefore, we suggest that Pipile should be merged with Aburria, which is the oldest described genus. We estimated that speciation in this group occurred in the Plio-Pleistocene, concordant with other birds, primates and rodents that have similar geographic distribution, and proposed a diversification hypothesis based on the occurrence of sea transgressions and the formation of the Amazon Lagoon. Therefore, we conclude that these palaeogeographic events may have contributed to Neotropical taxa diversification to a greater extent than previously suspected.  相似文献   

12.
A phylogenetic hypothesis of relationships among 33 species of stalk-eyed flies was generated from a molecular data set comprising three mitochondrial and three nuclear gene regions. A combined analysis of all the data equally weighted produced a single most-parsimonious cladogram with relatively strong support at the majority of nodes. The phylogenetic utility of different classes of molecular data was also examined. In particular, using a number of different measures of utility in both a combined and separate analysis framework, we focused on the distinction between mitochondrial and nuclear genes and between faster-evolving characters and slower-evolving characters. For the first comparison, by nearly any measure of utility, the nuclear genes are substantially more informative for resolving diopsid relationships than are the mitochondrial genes. The nuclear genes exhibit less homoplasy, are less incongruent with one another and with the combined data, and contribute more support to the combined analysis topology than do the mitochondrial genes. Results from the second comparison, however, provide little evidence of a clear difference in utility. Despite indications of rapid divergence and saturation, faster-evolving characters in both the nuclear and mitochondrial data sets still provide substantial phylogenetic signal. In general, inclusion of the more rapidly evolving data consistently improves the congruence among partitions.  相似文献   

13.
Right whales (genus: Eubalaena) are among the most endangered mammals, yet their taxonomy and phylogeny have been questioned. A phylogenetic hypothesis based on mitochondrial DNA (mtDNA) variation recently prompted a taxonomic revision, increasing the number of right whale species to three. We critically evaluated this hypothesis using sequence data from 13 nuclear DNA (nuDNA) loci as well as the mtDNA control region. Fixed diagnostic characters among the nuclear markers strongly support the hypothesis of three genetically distinct species, despite lack of any diagnostic morphological characters. A phylogenetics analysis of all data produced a strict consensus cladogram with strong support at nodes that define each right whale species as well as relationships among species. Results showed very little conflict among the individual partitions as well as congruence between the mtDNA and nuDNA datasets. These data clearly demonstrate the strength of using numerous independent genetic markers during a phylogenetics analysis of closely related species. In evaluating phylogenetic support contributed by individual loci, 11 of the 14 loci provided support for at least one of the nodes of interest to this study. Only a single marker (mtDNA control region) provided support at all four nodes. A study using any single nuclear marker would have failed to support the proposed phylogeny, and a strong phylogenetic hypothesis was only revealed by the simultaneous analysis of many nuclear loci. In addition, nu DNA and mtDNA data provided complementary levels of support at nodes of different evolutionary depth indicating that the combined use of mtDNA and nuDNA data is both practical and desirable.  相似文献   

14.
15.
A phylogenetic analysis for five Ponto-Caspian goby species belonging to the two genera Neogobius and Proterorhinus assigned to the sub-family Gobionellinae was conducted, with five Atlantic—Mediterranean species of sub-family Gobiinae, genera Gobius and Zosterisessor , as outgroup taxa. One hundred and two characters (37 continuous cranial osteological, 50 continuous external morphological, five discrete external morphological, four karyological, two vertebral and four external discrete qualitative characters) were studied. Parsimony analysis revealed that the two zoogeographically distinct groups of goby species comprise distinct phyletic lineages that are sister groups. The relation of neogobiids to the sub-family Gobiinae was reconsidered, due to the sharing of the same state for the diagnostic character. The recently proposed classification for the genera Proterorhinus and Zosterisessor was rejected. The status of several of the lower ranked taxa was also considered [e.g. Gobius bucchichi as a member of the genus Zosterisessor and the sub-generic status of Neogobius (Neogobius) fluviatilis and Neogobius ( Apollonia ) melanostomus ]. The paleohistorical data suggest that those lineages, which may both descend from pre-Oligocene Indo-Pacific ancestors, separated at least 12 million years ago, during the early Miocene, after the formation of the Paratethys Sea, and then evolved independently. The Tethyan gobiine species evolved in the marine environment of the Mediterranean Sea and the Atlantic Ocean. The Ponto-Caspian (i.e. Paratethyan) gobies of the genera Neogobiusa and Proterorhinus diverged in the late Miocene or early Pliocene. They probably evolved in the freshwater refuge in the Daccian Basin of the Paratethys Sea (the recent Black Sea basin).  相似文献   

16.
The Cracidae is one of the most endangered bird families in the World. Several studies have been published recently on the evolution and conservation of cracids. Phylogenetic analyses using a fragment of 661 bp of the mitochondrial cytochrome b gene for 39 different species of cracids corroborated most relationships found in previous studies. The present work attempts to refine the former phylogenetic hypothesis by increasing taxon sampling and combining molecular with osteological, integumentary and behavioural characters using Maximum Parsimony (MP) and Bayesian analyses. We present both separate and combined total evidence analyses with our molecular data, 152 osteological and 74 integumentary + behavioural characters. While supporting most aspects of the molecular-based hypotheses, the tree based on the combined matrix suggests several modifications of the generic composition for each of the two subfamilies: Penelopinae and Cracinae, and supports the merging of the genera Pipile with Aburria and Mitu with Pauxi . These results suggest that increased taxon and character sampling from a diversity of sources may be at least as important as increased sampling of only one type. Besides, of a total of 891 characters we had 437 parsimony-informative sites (almost half of the analyzable sites) proving the efficiency of a total-evidence approach.  相似文献   

17.
Euptychiina is the most species‐rich subtribe of Neotropical Satyrinae, with over 450 known species in 47 genera (14 monotypic). Here, we use morphological characters to examine the phylogenetic relationships within Euptychiina. Taxonomic sampling included 105 species representing the majority of the genera, as well as five outgroups. A total of 103 characters were obtained: 45 from wing pattern, 48 from genitalia and 10 from wing venation. The data matrix was analysed using maximum parsimony under both equal and extended implied weights. Euptychiina was recovered as monophyletic with ten monophyletic genera, contrasting previous DNA sequence‐based phylogenies that did not recover the monophyly of the group. In agreement with sequence‐based hypotheses, however, three main clades were recognized: the ‘Megisto clade’ with six monophyletic and three polyphyletic genera, the ‘Taygetis clade’ with nine genera of which three were monophyletic, and the ‘Pareuptyhia clade’ with four monophyletic and two polyphyletic genera. This is the first morphology‐based phylogenetic hypothesis for Euptychiina and the results will be used to complement molecular data in a combined analysis and to provide critical synapomorphies for clades and genera in this taxonomically confused group.  相似文献   

18.
Recent discoveries of new fossil hominid species have been accompanied by several phylogenetic hypotheses. All of these hypotheses are based on a consideration of hominid craniodental morphology. However, Collard and Wood (2000) suggested that cladograms derived from craniodental data are inconsistent with the prevailing hypothesis of ape phylogeny based on molecular data. The implication of their study is that craniodental characters are unreliable indicators of phylogeny in hominoids and fossil hominids but, notably, their analysis did not include extinct species. We report here on a cladistic analysis designed to test whether the inclusion of fossil taxa affects the ability of morphological characters to recover the molecular ape phylogeny. In the process of doing so, the study tests both Collard and Wood's (2000) hypothesis of character reliability, and the several recently proposed hypotheses of early hominid phylogeny. One hundred and ninety-eight craniodental characters were examined, including 109 traits that traditionally have been of interest in prior studies of hominoid and early hominid phylogeny, and 89 craniometric traits that represent size-corrected linear dimensions measured between standard cranial landmarks. The characters were partitioned into two data sets. One set contained all of the characters, and the other omitted the craniometric characters. Six parsimony analyses were performed; each data set was analyzed three times, once using an ingroup that consisted only of extant hominoids, a second time using an ingroup of extant hominoids and extinct early hominids, and a third time excluding Kenyanthropus platyops. Results suggest that the inclusion of fossil taxa can play a significant role in phylogenetic analysis. Analyses that examined only extant taxa produced most parsimonious cladograms that were inconsistent with the ape molecular tree. In contrast, analyses that included fossil hominids were consistent with that tree. This consistency refutes the basis for the hypothesis that craniodental characters are unreliable for reconstructing phylogenetic relationships. Regarding early hominids, the relationships of Sahelanthropus tchadensis and Ardipithecus ramidus were relatively unstable. However, there is tentative support for the hypotheses that S. tchadensis is the sister taxon of all other hominids. There is support for the hypothesis that A. anamensis is the sister taxon of all hominids except S. tchadensis and Ar. ramidus. There is no compelling support for the hypothesis that Kenyanthropus platyops shares especially close affinities with Homo rudolfensis. Rather, K. platyops is nested within the Homo + Paranthropus + Australopithecus africanus clade. If K. platyops is a valid species, these relationships suggest that Homo and Paranthropus are likely to have diverged from other hominids much earlier than previously supposed. There is no support for the hypothesis that A. garhi is either the sister taxon or direct ancestor of the genus Homo. Phylogenetic relationships indicate that Australopithecus is paraphyletic. Thus, A. anamensis and A. garhi should be allocated to new genera.  相似文献   

19.
20.
The Archiborborinae is a diverse Neotropical subfamily of Sphaeroceridae, with many undescribed species. The existing generic classification includes three genera consisting of brachypterous species, with all other species placed in the genus Archiborborus. We present the first phylogenetic hypothesis for the subfamily based on morphological, molecular, and combined datasets. Morphological data include 53 characters and cover all valid described taxa (33 species in 4 genera) in the subfamily, as well as 83 undescribed species. Molecular data for five genes (mitochondrial 12S rDNA, cytochrome c oxidase subunit I, and cytochrome B, and nuclear alanyl-tRNA synthetase and 28S rDNA) were obtained for 21 ingroup taxa. Data support the separation of the Archiborborinae from the Copromyzinae, with which they were formerly combined. Analyses support consistent groups within the subfamily, but relationships between groups are poorly resolved. The validity of the brachypterous genera Penola Richards and Frutillaria Richards is supported. The former genus Archiborborus Duda is paraphyletic, and will be divided into monophyletic genera on the basis of this work. Aptery and brachyptery have evolved multiple times in the subfamily. Antrops Enderlein, previously including a single brachypterous species, is a senior synonym of Archiborborus.  相似文献   

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