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1.
The Characinae is a subunit of the Characidae of special significance in including Charax, the type genus of the family and the order Characiformes. Twelve genera and 79 species have been traditionally assigned to the Characinae, but the subfamily still lacks a phylogenetic diagnosis. Herein, a data matrix including 150 morphological characters and 64 taxa (35 species representing all genera of the Characinae and 29 included in other lineages within the Characiformes) was submitted to two cladistic analyses that differ in the inclusion/exclusion of Priocharax due to the difficulty of coding most of the character states in the miniature species of this genus. Both analyses resulted in a non‐monophyletic Characinae and this subfamily is herein restricted to only seven of the original 12 genera forming the clade (Phenacogaster((Charax Roeboides)(Acanthocharax(Cynopotamus(Acestrocephalus Galeocharax))))), which is supported by ten non‐ambiguous synapomorphies and is more closely related to other genera of the Characidae than those traditionally placed in the subfamily. A second clade includes the members of the tribe Heterocharacini (Lonchogenys(Heterocharax Hoplocharax)) as the sister‐group of Gnathocharax, supported by seven non‐ambiguous synapomorphies. This clade is more closely related to a taxon formed by Roestes and Gilbertolus based on seven non‐ambiguous synapomorphies. Results do not corroborate a close relationship between RoestesGilbertolus and the Cynodontinae. Inclusion of the genus Priocharax suggests that it is related more closely to the Heterocharacini, but the profound modifications in its anatomy possibly related to ontogenetic truncations obscure a better understanding of its relationships. A new classification of the Characinae and the Heterocharacinae is proposed. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 809–915.  相似文献   

2.
The Marcetia alliance of Melastomataceae is an exclusively Neotropical group that includes at least 12 genera of mostly herbs and subshrubs, occurring in the cerrado of central Brazil and savannas of the Amazon region and Guayana highlands. This study aimed to test the monophyly of genera in the Marcetia alliance, evaluate their phylogenetic relationships and generic boundaries, and investigate morphological characters as potential synapomorphies for delimiting clades or genera. We used nuclear (ITS, ETS) and plastid (accD‐psaI, atpH‐atpF, trnS‐trnG) DNA sequences of 107 terminals in 12 genera from the alliance. Aciotis, Fritzschia, Marcetia and Siphanthera were shown to be monophyletic and supported by molecular and morphological characters. Other genera with variable morphology and wider distributions, such as Acisanthera, Comolia, Ernestia and Macairea, were recovered as paraphyletic or polyphyletic. Most morphological characters analysed were found to be homoplastic, but when combined they are potentially useful for the diagnosis of genera and infrageneric groups. This study represents a major step in understanding internal relationships and provides the basis for a revision of the generic classification in the Marcetia alliance.  相似文献   

3.
The genus Curcuma L. is commonly used as spices, medicines, dyes and ornamentals. Owing to its economic significance and lack of clear‐cut morphological differences between species, this genus is an ideal case for developing DNA barcodes. In this study, four chloroplast DNA regions (matK, rbcL, trnH‐psbA and trnL‐F) and one nuclear region (ITS2) were generated for 44 Curcuma species and five species from closely related genera, represented by 96 samples. PCR amplification success rate, intra‐ and inter‐specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in matK (89.7%), rbcL (100%), trnH‐psbA (100%), trnL‐F (95.7%) and ITS2 (82.6%) regions. The results further showed that four candidate chloroplast barcoding regions (matK, rbcL, trnH‐psbA and trnL‐F) yield no barcode gaps, indicating that the genus Curcuma represents a challenging group for DNA barcoding. The ITS2 region presented large interspecific variation and provided the highest correct identification rates (46.7%) based on BLASTClust method among the five regions. However, the ITS2 only provided 7.9% based on NJ tree method. An increase in discriminatory power needs the development of more variable markers.  相似文献   

4.
DNA barcoding aims to develop an efficient tool for species identification based on short and standardized DNA sequences. In this study, the DNA barcode paradigm was tested among the genera of the tribe Sisyrinchieae (Iridoideae). Sisyrinchium, with more than 77% of the species richness in the tribe, is a taxonomically complex genus. A total of 185 samples belonging to 98 species of Sisyrinchium, Olsynium, Orthrosanthus and Solenomelus were tested using matK, trnHpsbA and internal transcribed spacer (ITS). Candidate DNA barcodes were analysed either as single markers or in combination. Detection of a barcoding gap, similarity‐based methods and tree‐based analyses were used to assess the discrimination efficiency of DNA barcodes. The levels of species identification obtained from plastid barcodes were low and ranged from 17.35% to 20.41% for matK and 5.11% to 7.14% for trnH‐psbA. The ITS provided better results with 30.61–38.78% of species identified. The analyses of the combined data sets did not result in a significant improvement in the discrimination rate. Among the tree‐based methods, the best taxonomic resolution was obtained with Bayesian inference, particularly when the three data sets were combined. The study illustrates the difficulties for DNA barcoding to identify species in evolutionary complex lineages. Plastid markers are not recommended for barcoding Sisyrinchium due to the low discrimination power observed. ITS gave better results and may be used as a starting point for species identification.  相似文献   

5.
The aim of the present work was to clarify the origin and phylogenetic position of the species belonging to the genus Ilex (Aquifoliaceae), especially the South American species. Phylogenetic relationships of the genus Ilex were investigated using the plastid psbA‐trnH intergenic spacer and parsimony and Bayesian analyses. The psbAtrnH intergenic spacer was shown to evolve slowly within Ilex, but a major gap present in this region was useful in the phylogenetic study of the genus. To obtain more potentially parsimonious characters, atpB‐rbcL intergenic spacer data were combined with those for psbA‐trnH. Many gaps present in the psbA‐trnH region were useful in the phylogenetic study of the genus Ilex. The topology of the trees showed that, in general, the clades are strongly related to geographical areas, a fact especially evident in certain different Asian lineages. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 182–193.  相似文献   

6.
Abstract Four DNA barcoding loci, chloroplast loci rbcL, matK, trnH‐psbA, and nuclear locus internal transcribed spacer (ITS), were tested for the accurate discrimination of the Chinese species of Gaultheria by using intraspecific and interspecific pairwise P‐distance, Wilcoxon signed rank test, and tree‐based analyses. This study included 186 individuals from 89 populations representing 30 species. For all individuals, single locus markers showed high levels of sequencing universality but were ineffective for species resolvability. Polymerase chain reaction amplification and sequencing were successful for all four loci. Both ITS and matK showed significantly higher levels of interspecific species delimitation than rbcL and trnH‐psbA. A combination of matK and ITS was the most efficient DNA barcode among all studied regions, however, they do not represent an appropriate candidate barcode for Chinese Gaultheria, by which only 11 out of 30 species can be separated. Loci rbcL, matK, and trnH‐psbA, which were recently proposed as universal plant barcodes, have a very poor capacity for species separation for Chinese Gaultheria. DNA barcodes may be reliable tools to identify the evolutionary units of this group, so further studies are needed to develop more efficient DNA barcodes for Gaultheria and other genera with complicated evolutionary histories.  相似文献   

7.
Abstract One application of DNA barcoding is species identification based on sequences of a short and standardized DNA region. In plants, various DNA regions, alone or in combination, have been proposed and investigated, but consensus on a universal plant barcode remains elusive. In this study, we tested the utility of four candidate barcoding regions (rbcL, matK, trnHpsbA, and internal transcribed spacer (ITS)) as DNA barcodes for discriminating species in a large and hemiparasitic genus Pedicularis (Orobanchaceae). Amplification and sequencing was successful using single primer pairs for rbcL, trnH‐psbA, and ITS, whereas two primer pairs were required for matK. Patterns of sequence divergence commonly showed a “barcoding gap”, that is, a bimodal frequency distribution of pairwise distances representing genetic diversity within and between species, respectively. Considering primer universality, ease of amplification and sequencing, and performance in discriminating species, we found the most effective single‐region barcode for Pedicularis to be ITS, and the most effective two‐region barcode to be rbcL + ITS. Both discriminated at least 78% of the 88 species and correctly identified at least 89% of the sequences in our sample, and were effective in placing unidentified samples in known species groups. Our results suggest that DNA barcoding has the potential to aid taxonomic research in Pedicularis, a species‐rich cosmopolitan clade much in need of revision, as well as ecological studies in its center of diversity, the Hengduan Mountains region of China.  相似文献   

8.
Deparia, including the previously recognized genera Lunathyrium, Dryoathyrium (=Parathyrium), Athyriopsis, Triblemma, and Dictyodroma, is a fern genus comprising about 70 species in Athyriaceae. In this study, we inferred a robust Deparia phylogeny based on a comprehensive taxon sampling (~81% of species) that captures the morphological diversity displayed in the genus. All Deparia species formed a highly supported monophyletic group. Within Deparia, seven major clades were identified, and most of them were characterized by inferring synapomorphies using 14 morphological characters including leaf architecture, petiole base, rhizome type, soral characters, spore perine, and leaf indument. These results provided the morphological basis for an infra‐generic taxonomic revision of Deparia.  相似文献   

9.
A phylogeny of the hummingbirds of the genera Ramphodon, Eutoxeres, Glaucis, Threnetes, and Phaethornis is presented on the basis of external morphological characters. All 34 species of hermit hummingbirds are included in this study. Differences in 96 characters were examined with regard to their apomorphic (derived) or plesiomor‐phic (primitive) states, resulting in evolutionary trees drawn on the basis of cladistic principles. The most important results are: (1) “Ramphodondohrnii is closer to Glaucis than to Ramphodon; (2) “Phaethornis” gounellei is the sister species to all Phaethornis and merits reevaluation as a separate genus, Anopetia; (3) Phaethornis philippii and P. koepckeae are the sister group to P. syrmatophorus, their straight bill having evolved independently of P. bourcieri; (4) the Phaethornis superciliosus/malaris species group includes P. longirostris as a third species; (5) Phaethornis subochraceus, P. pretrei, and P. augusti share a common ancestor, and (6) Phaethornis longuemareus (sensu Peters 1945) is polyphyletic, being comprised of four seperate species. Due to the lack of synapomorphies, the relationships of some species cannot be reliably determined on the basis of external morphological characters alone.  相似文献   

10.
Shrimps of the genus Palaemon Weber, 1795 comprise of 86 species with a wide morphological and ecological variability along the tropical and temperate regions. Studies based on molecular data have indicated that despite a recent taxonomic rearrangement, it may remain not monophyletic. On the other hand, cladistic, morphological analyses have suggested the presence of synapomorphies, implying a natural status for the genus. In this work, a broad taxonomic and molecular sampling is applied to verify whether Palaemon is a monophyletic taxon and, based on the recovered phylogeny, identify geographical and morphological patterns related to the lineages. Partial sequences of 16S rRNA, histone H3 and 18S rRNA from 60 species of Palaemon and 15 species from other genera of Palaemonidae were analysed. In addition, previously used characters as well as novel diagnostic characters were scrutinized. The present phylogeny indicates that the species of Palaemon fall into three distinct lineages and that the colonization of America and Europe likely occurred multiple times. Morphological characters allow for the identification of at least four monophyletic groups in Palaemon; two of which are monospecific at the moment. Based on the present results, it may become necessary to establish two new genera (to accommodate Palaemon concinnus and Palaemon mercedae, respectively), as well as re‐erect the genus Alaocaris Holthuis, 1949 for Palaemon antrorum, potentially including a further six American species.  相似文献   

11.
The five mint genera Brazoria, Macbridea, Physostegia, Synandra and Warnockia (Lamioideae: Lamiaceae) are all North American endemics. Together with the monotypic European genus Melittis and the Asian genus Chelonopsis, these taxa have been classified as subtribe Melittidinae. Previous morphological studies have failed to uncover synapomorphic characters for this group. We sequenced the plastid trnL‐trnF region and trnS‐trnG spacer and the nuclear ribosomal 5S non‐transcribed spacer (5S‐NTS) to assess phylogenetic relationships within Melittidinae. Standard parsimony and direct optimization (POY) analyses show Melittis, the type genus of the subtribe, as sister to Stachys. Thus, the monophyly of subtribe Melittidinae is not supported either by molecular or morphological data. However, the North American endemics form a monophyletic group that can be recognized as the recircumscribed tribe Synandreae. The molecular relationships among these genera are corroborated by both morphological and cytological data. The expected close relationship between the south‐central endemics Warnockia and Brazoria and their sister relationship to the widespread genus Physostegia is confirmed. Nevertheless, most of the North American endemics are restricted to the south‐east of the continent. Dispersal westwards and northwards is correlated with an increase in chromosome numbers. No specific Eurasian origin (i.e., transatlantic or transpacific) can be determined, but Synandreae are clearly distinct from the large Stachys clade, and therefore represent a separate migration into North America. © The Willi Hennig Society 2007.  相似文献   

12.
The family Rhinocryptidae comprises an assemblage of 12 genera and 55 species confined to the Neotropical region. Here we present the first morphology‐based phylogenetic study of the Rhinocryptidae, using 90 anatomical characters (62 osteological, 28 syringeal) scored for all genera of the family and representatives of all families of the infraorder Furnariides. Parsimony analysis of this dataset recovered 7428 equally most‐parsimonious trees. The strict consensus of those trees was completely resolved at the genus level, with the topology (Liosceles (Psilorhamphus ((Eleoscytalopus + Merulaxis) (Acropternis ((Teledromas + Rhinocrypta) ((Pteroptochos + Scelorchilus) (Eugralla (Myornis + Scytalopus)))))))). The monophyly of the Rhinocryptidae as presently understood was recovered with strong support [eight synapomorphies and Bremer support (BS) = 6). Strongly supported internal arrangements included the basal position of the Amazonian genus Liosceles relative to the rest of the family (four synapomorphies, BS = 4), a clade containing Acropternis through Scytalopus (six synapomorphies, BS = 4), and other less inclusive nodes. The main points of congruence between the present morphological phylogeny and previous molecular phylogenetic work on the family were clades supported by six or more synapomorphies and Bremer values of 6–7: Eleoscytalopus + Merulaxis (eight synapomorphies, BS = 6), Scelorchilus + Pteroptochos (seven synapomorphies, BS = 7), Rhinocrypta + Teledromas (seven synapomorphies, BS = 7), and Eugralla + Myornis + Scytalopus (six synapomorphies, BS = 6). A classification derived from the morphological phylogeny is proposed, with new suprageneric taxa being named and diagnosed. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 377–432.  相似文献   

13.
Myrtaceae are one of the most species‐rich families of flowering plants in the Neotropics. They include several complex genera and species; Hexachlamys is one of the complex genera. It has not been recognized as a distinct genus and has been included in Eugenia, based on morphological grounds. Therefore, molecular systematic studies may be useful to understand and to help to solve these relationships. Here, we performed a molecular phylogenetic analysis using plastid and nuclear data in order to check the inclusion of Hexachlamys in Eugenia. Plastid (accD, rpoB, rpoC1, trnH‐psbA) and nuclear (ITS2) sequence data were analysed using Bayesian and maximum parsimony methods. The trees constructed using ITS2 and trnH‐psbA were the best able to resolve the relationships between species and genera, revealing the non‐monophyly of Hexachlamys. The molecular phylogenetic analyses were in agreement with previous morphological revisions that have included Hexachlamys in Eugenia. These results reinforce the importance of uniting knowledge and strategies to understand better issues of delimitation of genera and species in groups of plants with taxonomic problems. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 532–543.  相似文献   

14.
15.
The gastric teeth of three ocypodoid species were investigated using scanning electron microscopy, and the morphological results were discussed with respect to the known food preferences. The species were chosen in particular because of contrasting ideas about their relationships within the Thoracotremata. For the genera Heloecius, Dotilla, Mictyris, and “Uca” (s. str.), we find a specific correlation of the gastric teeth with the suspension feeding. The lateral gastric teeth of Uca have no prominent lateral teeth cusps, and most of their teeth surface consists of transverse comb‐like lamellae. However, this possible food adaptation does not exclude the usability of specific teeth characters to distinguish species of suspension feeders. The closer relationship of the Dotillidae to grapsoid lines of gecarcinid or sesarmid crabs suggested by molecular data is not supported by the gastric teeth. For the genus Ucides, we found several characters that distinguish Ucides from the remaining ocypodoid genera Heloecius, Dotilla, Mictyris, and “Uca.” In particular, the structures of the lateral and the dorsomedian teeth show some similarities to genera of the Gecarcinidae and Sesarmidae. Our results suggest that foregut characters can be used for phylogenetic analyses. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

16.
The classification and generic definition in the tropical–subtropical fern family Lindsaeaceae have been uncertain and have so far been based on morphological characters only. We have now studied the evolutionary history of the Lindsaeaceae by simultaneously optimizing 55 morphological characters, two plastid genes (rpoC1 and rps4) and three non‐coding plastid intergenic spacers (trnL‐F, rps4‐trnS and trnH‐psbA). Our data set included all genera associated with Lindsaeaceae, except Xyropteris, and c. 73% of the currently accepted species. The phylogenetic relationships of the lindsaeoid ferns with two enigmatic genera that have recently been included in the Lindsaeaceae, Cystodium and Lonchitis, remain ambiguous. Within the monophyletic lindsaeoids, we found six well‐supported and diagnostic clades that can be recognized as genera: Sphenomeris, Odontosoria, Osmolindsaea, Nesolindsaea, Tapeinidium and Lindsaea. Sphenomeris was shown to be monotypic; most taxa formerly placed in that genus belong to the Odontosoria clade. Ormoloma is embedded within Lindsaea and therefore does not merit recognition as a genus. Tapeinidium is sister to a clade with some species formerly placed in Lindsaea that are morphologically distinct from that genus and are transferred to Osmolindsaea and Nesolindsaea, proposed here as two new genera. We do not maintain the current subgeneric classification of Lindsaea itself, because neither of the two generally accepted subgenera (Lindsaea and Odontoloma) is monophyletic, and most of the sections also appear unnatural. Nesolindsaea shows an ancient biogeographical link between Sri Lanka and the Seychelles and many of the main clades within Lindsaea have geographically disjunct distributions. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 305–359.  相似文献   

17.
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   

18.
The Grapsidae are a thoracotreme crab family with 40 species in eight genera (in their strict definition), and possess a number of morphological and molecular synapomorphies. Previous phylogenetic studies based on mitochondrial DNA markers established the monophyly of this family, but suggested possible paraphyly or polyphyly of some of the constituent genera. To test the validity of previous hypotheses, the present study reconstructed a molecular phylogeny of the grapsid crabs based on five molecular markers, including mitochondrial DNA markers and the first use of nuclear protein‐coding markers to address this issue. Monophyly of Grapsidae was confirmed, with the exception of the position of the monotypic genus Leptograpsodes. The polyphyly of the genus Pachygrapsus is consistent with previous molecular phylogenies, as members from this genus are dispersed throughout our gene tree. Grapsus and Planes were shown to be paraphyletic, with species of Pachygrapsus nested within them. Our study found incongruences between the currently adopted classification of the family, and hence taxonomic revisions will be needed. We hereby demonstrate the use of nuclear protein‐coding markers for high confidence reconstruction of decapod phylogenies, resolving most of the early splits that mitochondrial DNA markers alone are unable to tackle. © 2015 The Linnean Society of London  相似文献   

19.
Abstract Chirita D. Don, a large genus in the subfamily Cyrtandroideae of Gesneriaceae, has been the subject of much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL‐F for molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artificial, polyphyletic genus. The most important character that defines Chirita, the dorso‐ventrally oblique and bilamellar stigma, has evolved convergently in different clades of diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of Chirita. The species of Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea form a monophyletic group that is sister to a strongly supported clade comprising four monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We further analyzed the morphological evolution of Chirita and identified a series of morphological synapomorphies for the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.  相似文献   

20.
Abstract. Larvae of the scarabaeoid genera Germarostes Paulian, Cyphopisthes Gestro, Paulianostes Ballerio, Ceratocanthus White, Pterorthochaetes Gestro, Madrasostes Paulian, Astaenomoechus Martínez & Pereira (Ceratocanthidae) and Hybosorus Macleay, Phaeochrous Castelnau, and Anaides Westwood (Hybosoridae) are described, keyed and illustrated with fifty‐seven drawings. A phylogenetic analysis of these two families based on larval morphology is presented. Fifty‐four larval morphological and three biological characters from twenty‐seven taxa revealed nineteen equally parsimonious cladograms. The monophyly of (Ceratocanthidae + Hybosoridae) is supported by four unambiguous unique synapomorphies: dorsal medial endocarina on cranium extended anteriorly into frontal sclerite; presence of large membranous spot on apical antennomere; labium dorsally with four pores in centre (secondarily reduced to two pores in some groups); and presence of stridulatory organ on fore‐ and middle legs (secondarily reduced in some groups). Our analysis suggests that the family Hybosoridae is paraphyletic with respect to Ceratocanthidae. The clade comprising the hybosorid genera Hybosorus and Phaeochrous is the sister group of the remaining Hybosoridae plus Ceratocanthidae. It is supported by two unambiguous synapomorphies: two apical antennomeres completely joined and the stridulatory organ represented by seven to nine large teeth anteriorly on the middle leg. The hybosorid genus Anaides is a sister group to the remaining Hybosoridae plus Ceratocanthidae (without Hybosorus and Phaeochrous) and the ceratocanthid genus Germarostes is a sister group to the remaining Hybosoridae plus Ceratocanthidae (without Hybosorus, Phaeochrous and Anaides). The ceratocanthid genera Cyphopisthes, Astaenomoechus, Paulianostes, Pterorthochaetes, and Madrasostes constitute a sister group to the hybosorid genus Cryptogenius and are supported by the presence of two reversions: two dorsal pores on labium and completely reduced stridulatory organs on fore‐ and middle legs.  相似文献   

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