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1.
A phylogenetic estimation of the temperate Gondwanan mite harvestman family Pettalidae (Arachnida, Opiliones, Cyphophthalmi) was conducted using 143 morphological variables (59 raw and 84 scaled measurements) from 37 ingroup and 15 outgroup terminals. We used custom algorithms to do pairwise comparisons between characters and identify sets of dependent characters, which were collapsed using principal components analysis. We analysed the resulting data without discretization under the parsimony criterion. Monophyly or paraphyly of most groups suspected from previous molecular and morphological phylogenetic studies were recovered. Trees were optimized for monophyly of 20 different focus clades by varying character phylogenetic independence. This yielded a final tree with monophyly of 15 out of 20 focus clades, including the South African pettalids, which contains the troglomorphic species Speleosiro argasiformis Lawrence, 1931. Two of the remaining five clades were found paraphyletic, with the genera Aoraki, Rakaia, and Siro always being found polyphyeletic.  相似文献   

2.
The Lejeuneaceae are the largest family of the liverworts (Hepaticae), with almost a thousand species in 91 currently accepted genera. We analysed phylogenetic relationships of 69 genera, representing all major subfamilies and tribes recognized in the family, by using 49 informative morphological characters (31 gametophytic, 18 sporophytic), one chemical character, and applying equal and successive weighting of characters and parsimony analysis. In all trees recovered, the Lejeuneaceae were monophyletic with Nipponolejeunea (subfam. Nipponolejeuneoideae) forming the basalmost lineage. The remaining genera clustered in two major groups, the monophyletic Lejeuneoideae (52 genera) and the paraphyletic Ptychanthoideae (16 genera). Within each, several multigeneric lineages corresponding in part to previously described taxa were recovered: the Acrolejeuneinae and Ptychanthinae clades in the Ptychanthoideae, and the Brachiolejeuneinae, Lejeuneeae and Tuyamaella–Cololejeunea clades in the Lejeuneoideae. Bryopteris , a genus sometimes treated as a separate family, was nested in the Ptychanthinae clade. The Tuyamaella–Cololejeunea lineage corresponded with three previously recognized subfamilies (Cololejeuneoideae, Myriocoleoideae and Tuyamaelloideae) and contained genera with neotenic features, in two subclades. These features seemed to have originated by multiple heterochronic events: single origins were detected for 'protonemal neoteny' and 'primary neoteny', whereas 'secondary neoteny' probably evolved twice. Relationships within the large Lejeuneeae clade (43 genera) remained largely unresolved, although several putative lineages were detected in majority rule trees. Additional characters such as DNA sequences may provide better phylogenetic resolution in this group.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 391–410.  相似文献   

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The morphology of the acrophallus, the distal portion of the male phallus carrying the phallotreme, was studied in 72 exemplar species representing 56 genera and subgenera of the flesh fly subfamily Sarcophaginae. For 42 of those species, scanning electron microscopy was used to clarify the phallic morphology. Terms used to describe the male genitalia were updated based on new interpretations of homology. Male genitalic characters, combined with other morphological characters of adult males and females and of larvae, were used to construct a phylogeny. The monophyly of the subfamily was supported, and some generic‐level sister‐group relationships proposed in the literature, but without previous cladistic analyses, were also supported. The genus Blaesoxipha Loew, as currently recognized, was not monophyletic in our analysis. The genus Helicobia Coquillett is synonymized with Sarcophaga Meigen syn. nov. and treated as a subgenus of the latter. The Sarcophaga subgenera Neobellieria Blanchard and Mehria Enderlein were not monophyletic. Many of the clades in the analysis were supported primarily or exclusively by male genitalic character states, highlighting the importance of the male genitalia as a source of morphological characters for sarcophagine phylogeny. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 740–778.  相似文献   

5.
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   

6.
The sturgeon subfamily Scaphirhynchinae contains two genera of obligate freshwater sturgeon: Scaphirhynchus and Pseudoscaphirhynchus, from North America and Central Asia, respectively. Both genera contain morphologically variable species. A novel data set containing multiple individuals representing four diagnosable morphological variants for two species of Pseudoscaphirhynchus, P. hermanni and P. kaufmanni, was generated. These data were used to test taxonomic hypotheses of monophyly for the subfamily Scaphirhynchinae, monophyly of both Scaphirhynchus and Pseudoscaphirhynchus, monophyly of P. hermanni and P. kaufmanni, and monophyly of the recognized morphological variants. Monophyly of the subfamily Scaphirhynchinae is consistently rejected by all phylogenetic reconstruction methodologies with the molecular character set while monophyly of both river sturgeon genera is robustly supported. The molecular data set also rejects hypotheses of monophyly for sampled species of Pseudoscaphirhynchus as well as monophyly for the recognized intraspecific morphological variants. Interestingly both Scaphirhynchus and Pseudoscaphirhynchus demonstrate the same general pattern in reconstructed topologies; a lack of phylogenetic structure in the clade with respect to recognized diversity. Despite rejection of monophyly for the subfamily Scaphirhynchinae with molecular data, reconstructed hypotheses from morphological character sets consistently support monophyly for this subfamily. Disparities among the data sets, as well as reasons for rejection of monophyly for Scaphirhynchinae and species of Scaphirhynchus and Pseudoscaphirhynchus with molecular characters are examined and a decreased rate of molecular evolution is found to be most consistent with the data.  相似文献   

7.
Caecilian morphology is strongly modified in association with their fossorial mode of life. Currently phylogenetic analyses of characters drawn from the morphology of caecilians lack resolution, as well as complementarity, with results of phylogenetic analyses that employ molecular data. Stemming from the hypothesis derived from the mammal literature that the braincase has the greatest potential (in comparison to other cranial units) to yield phylogenetic information, the braincase and intimately associated stapes of 27 species (23 genera) of extant caecilians were examined using images assembled via microcomputed tomography. Thirty‐four new morphological characters pertaining to the braincase and stapes were identified and tested for congruence with previously recognized morphological characters. The results reveal that when added to previous character matrices, characters of the braincase and stapes resolve generic‐level relationships in a way that is largely congruent with the results of molecular analyses. Analysis of a combined data set of molecular and morphological data provides a framework for conducting ancestral character state reconstructions, which resulted in the identification of 95 new synapomorphies for various clades and taxa, 27 of which appear to be unique for the taxa that possess them. Together these data demonstrate the utility of the application of characters of the braincase and stapes for resolving phylogenetic relationships for a group whose morphology is largely confounded by functional modifications. In addition this study provides evidence of the utility of the braincase in resolving problematic morphology‐based phylogeny outside of Amniota, in an amphibian group. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 160–201.  相似文献   

8.
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   

9.
Chironius is one of the most speciose genera of the South American colubrid snakes. Although the genus represents a well‐known radiation of diurnal racers, its monophyly, affinities with other Neotropical colubrid genera, and intrageneric relationships are open questions. Here, we present a phylogenetic analysis of Chironius based on a data matrix that combines one nuclear (c‐mos) and two mitochondrial (12S and 16S rRNA) genes with 37 morphological characters derived from scutellation, skull, and hemipenial features. Phylogenetic relationships were inferred using maximum parsimony (MP) and maximum likelihood (ML). Our combined morphological and molecular analyses strongly support the monophyly of the genus Chironius and its sister‐group relationship with a clade formed by the genera Dendrophidion and Drymobius. Phylogenetic relationships within the genus Chironius is still controversial, although five clades are retrieved with medium to strong support. © 2014 The Linnean Society of London  相似文献   

10.
The first comprehensive phylogenetic analyses of the most diverse subfamily of plant bugs, Mirinae, is presented in this study, for 110 representative taxa based on total evidence analysis. A total of 85 morphological characters and 3898 bp of mitochondrial (16S, COI) and nuclear (18S, 28S) sequences were analysed for each partitioned and combined dataset based on parsimony, maximum likelihood and Bayesian inference. Major results obtained in this study include monophyly of the tribe Mecistoscelini. The largest tribe, Mirini, was recovered as polyphyletic, and Stenodemini was recovered as paraphyletic. The clade of Stenodemini + Mecistoscelini is the sister group of the remaining Mirinae. The monophyly of two complexes composed of superficially similar genera were tested; the Lygus complex was recovered as nonmonophyletic, and the Adelphocoris–Creontiades–Megacoelum complex was confirmed to be monophyletic. The generic relationships of the main clades within each tribe based on the phylogeny, as well as their supported morphological characters, are discussed.  相似文献   

11.
Phylogenetic relationships within the orchid subtribe Oncidiinae sensu Chase were inferred using maximum likelihood analyses of single and multilocus DNA sequence data sets. Analyses included both nuclear ribosomal internal transcribed spacer DNA and plastid regions (matK exon, trnH‐psbA intergenic spacer and two portions of ycf1 exon) for 736 individuals representing approximately 590 species plus seven outgroup taxa. Based on the well resolved and highly supported results, we recognize 61 genera in Oncidiinae. Mimicry of oil‐secreting Malpighiaceae and other floral syndromes evolved in parallel across the subtribe, and many clades exhibit extensive variation in pollination‐related traits. Because previous classifications heavily emphasized these floral features, many genera recognized were not monophyletic. Our classification based on monophyly will facilitate focused monographs and clarifies the evolution of morphological and biochemical traits of interest within this highly diverse subtribe. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 117–146.  相似文献   

12.
The taxonomic value and evolutionary significance of 30 leaf epidermal characters from 238 samples representing 127 species of all seven genera in the tribe Gaultherieae (Ericaceae) and two outgroup genera were investigated by scanning electron microscopy. The character states were coded and optimized onto a maximum‐likelihood tree based on previous molecular data with Fitch parsimony and hierarchical Bayesian analysis to trace the evolution of character states throughout all internodes in the phylogenetic tree for Gaultherieae. Leaf epidermal characters were found to be largely consistent within species, but highly variable at interspecific and higher taxonomic levels. The most recent common ancestral states of 15 characters diagnosed various lineages recovered from prior studies, some with no prior morphological support. Relatively high frequencies of state change occur in the eastern Asian clade Gaultheria series Gymnobotrys + Diplycosia, the American clade G. subsection Dasyphyta p.p., the core East Asian clade and the Australia/New Zealand clade. The characters with the highest frequencies of state change are the outer stomatal ledge ornamentation type, the stomatal apparatus level, stomatal density and area, and the type of abaxial trichomes. These character state change patterns may provide insight into the ecological adaptions of Gaultherieae during their evolutionary history. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 686–710.  相似文献   

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Ariid monophyly and intrafamilial relationships are investigated based on cladistic analysis of 230 morphological characters. Terminal taxa examined include whenever possible type‐species, or the most morphologically similar species to the type‐species of the nominal genera, and the largest possible number of species, including cleared and stained specimens, available in zoological collections. Previous hypotheses about monophyly of the Ariidae are strongly corroborated by new synapomorphies discovered in the present study. The subfamily Galeichthyinae and the remaining ariids are strongly supported by new morphological characters. The monotypic subfamily Bagreinae is recognized as the sister group to all nongaleichthyin ariids, supported by a large series of exclusive synapomorphies. A new concept of Ariinae is presented: the subfamily is found to be unequivocally monophyletic and includes all ariid genera, except Galeichthys and Bagre. New data supporting the monophyly of the genera included in the Ariinae are introduced and previous hypotheses of monophyly, species composition, morphological definition, and relationships are reviewed and discussed.  相似文献   

15.
Abstract We develop a morphological dataset for the rove beetle subfamily Euaesthetinae comprising 167 morphological characters (135 adult and 32 larval) scored from 30 terminal taxa including 25 ingroup terminals (from subfamilies Euaesthetinae and Steninae) and five outgroups. Four maximum parsimony analyses using different sets of terminals and character sets were run to test the monophyly of (1) Euaesthetinae, (2) Steninae, (3) Euaesthetinae + Steninae, (4) euaesthetine tribes Austroesthetini, Alzadaesthetini, Euaesthetini, Fenderiini and Stenaesthetini, and (5) the ten currently known austral endemic genera together. Analyses of adult and larval character sets separately and in combination recovered the monophyly of Euaesthetinae, Steninae, and both subfamilies together, with strong support. Analysis of 13 ingroup terminals for which complete data were available suggests that monophyly of Euaesthetinae is supported by 19 synapomorphies (13 adult, six larval), of Steninae by 23 synapomorphies (14 adult, nine larval), and of both subfamilies together by 24 synapomorphies (21 adult, three larval). Within Euaesthetinae, only the tribe Stenaesthetini was recovered as monophyletic based on adult characters, and in no analyses were the ten austral endemic genera recovered as a monophyletic group. Phylogenetic relationships among euaesthetine genera were weakly supported, although analyses including adult characters supported monophyly of Octavius and Protopristus separately, and of Octavius + Protopristus, Austroesthetus + Chilioesthetus and Edaphus + Euaesthetus. Steninae may include a third genus comprising two undescribed species probably possessing a ‘stick–capture’ method of prey capture, similar to that in Stenus. These two species formed a strongly supported clade recovered as the sister group of Stenus based on adult characters. Diagnoses and a key to adults are provided for the 15 euaesthetine genera currently known from the austral region (Australia, New Zealand, South Africa and southern South America). Euaesthetine larvae previously were known only for Euaesthetus, and we describe the larvae of nine more genera and provide the first larval identification key for genera of Euaesthetinae.  相似文献   

16.
The use of internal skeletal structures is valuable to phylogenetic reconstruction within Hymenoptera; however, these structures were not further investigated for Augochlorini. Previous phylogenetic studies of Augochlorini based only on external morphology were poorly resolved. The objectives of this work are to explore the comparative morphology of internal structures of the mesosoma and to evaluate their potential as information sources for the phylogenetic relationships within the tribe. The internal structures of the Pseudaugochlora graminea (Fabricius, 1804) mesosoma are described in detail and compared with 16 other genera. We propose 24 new character statements for the Augochlorini phylogeny based on internal structures of mesosoma. Prosternum, propleuron and meso/metafurca provided a great number of informative characters. On the other hand, the mesophragma, metanotum and propodeum were less variable. The monophyly of Augochlorini and of all genus groups was corroborated in a parsimony analysis of internal and external morphological characters. Characters derived from internal structures provided the first‐known morphological synapomorphies for the clades: Megaloptidia group + others, Neocorynura group + others and Augochlora group + Megalopta group. These characters helped to elucidate the evolution of the group when analysed together with external morphological characters.  相似文献   

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A higher level phylogeny for the passion-vine butterflies (Nymphalidae, Heliconiinae) was generated by cladistic analysis of 146 morphological characters from all life stages. The 24 species studied were selected representatives of the ten currently accepted genera of the sub-tribe Heliconiiti. Analyses of only characters from larvae and pupae did not produce well resolved trees. However, some characters of the immature stages provided critical support for the monophyly of two clades. Analysis of only adult characters yielded a tree that closely resembled that obtained from all data combined. The phylogeny here derived from the combined analysis of early stage and adult characters differed in topology from all previously proposed hypotheses, and supported the monophyly of all currently recognized genera. Characters supporting each clade are described and illustrated, and various hypotheses of phylogenetic relatedness of passion-vine butterfly taxa are discussed.  相似文献   

19.
Sequences of the ITS region of nrDNA were analyzed for the seven genera of Papaveraceae subf. Chelidonioideae s.str. Three major clades can be recognized. These are 1.Chelidonium/Hylomecon/Stylophorum, 2.Eomecon/Sanguinaria, and 3.Bocconia/Macleaya. The monophyly of genera in the first of these three clades is doubtful, and clades two and three are sister to each other. Use of the ITS phylogeny of the subfamily to trace its morphological and ecological evolution shows that morphological change is concentrated in theBocconia/Macleaya clade, and probably related to the evolution of wind-pollination from insect-pollination in these two genera after habitat shift.  相似文献   

20.

Background and Aims

The Neotropical tribe Trimezieae are taxonomically difficult. They are generally characterized by the absence of the features used to delimit their sister group Tigridieae. Delimiting the four genera that make up Trimezieae is also problematic. Previous family-level phylogenetic analyses have not examined the monophyly of the tribe or relationships within it. Reconstructing the phylogeny of Trimezieae will allow us to evaluate the status of the tribe and genera and to examine the suitability of characters traditionally used in their taxonomy.

Methods

Maximum parsimony and Bayesian phylogenetic analyses are presented for 37 species representing all four genera of Trimezieae. Analyses were based on nrITS sequences and a combined plastid dataset. Ancestral character state reconstructions were used to investigate the evolution of ten morphological characters previously considered taxonomically useful.

Key Results

Analyses of nrITS and plastid datasets strongly support the monophyly of Trimezieae and recover four principal clades with varying levels of support; these clades do not correspond to the currently recognized genera. Relationships within the four clades are not consistently resolved, although the conflicting resolutions are not strongly supported in individual analyses. Ancestral character state reconstructions suggest considerable homoplasy, especially in the floral characters used to delimit Pseudotrimezia.

Conclusions

The results strongly support recognition of Trimezieae as a tribe but suggest that both generic- and species-level taxonomy need revision. Further molecular analyses, with increased sampling of taxa and markers, are needed to support any revision. Such analyses will help determine the causes of discordance between the plastid and nuclear data and provide a framework for identifying potential morphological synapomorphies for infra-tribal groups. The results also suggest Trimezieae provide a promising model for evolutionary research.  相似文献   

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