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1.
The work represents the second part of the study pertaining to the definition of the genus Eurotestudo. The first part (Ann. Pal. 2006, 92 (3)) concentrated on the introduction to the subject and to the reporting of the morphological data, on which the definition is based. In this second part, results from the cladistic analysis are presented. All the results which are based on a morphological study, justifying the separation of three lineages previously included in Testudo s.l., are examined. External characters derived from extant forms, and congruent with the definition of the genus and its separation from two other taxa, Testudo and Agrionemys (which are redefined), are also presented. The text is followed by appendices listing the examined taxa and materials.  相似文献   

2.
《Palaeoworld》2023,32(1):116-123
The oldest fossils assigned to Athyrium (mostly based on the sorus morphology) comprise fronds and spores from the Lower Cretaceous of Northeast Asia. However, most molecular dating suggests that extant Athyrium diverged from its sister genus during the Eocene or later, implying that the Cretaceous fossils probably belong to another polypodiaceous taxon. By examining the sorus morphology of extant genera related to the family Athyriaceae, we found that the primary diagnostic feature for assigning the Cretaceous fossils to Athyrium, i.e., the sorus shape, is common to the entire extant family, or plesiomorphic for the genus. As the fronds are more commonly preserved than the reproductive parts, we compared the fossil frond morphology with those of living taxa of the family that is divided into two types. The Cretaceous fossil we examined here bears the frond’s costal groove characters on adaxial side, which is more closely related to that of the Deparia-clade instead of the clade including Athyrium and other genera of the family. The observation is further confirmed by the cladistic analysis using morphological characters. The systematic position of the Early Cretaceous “Athyrium” was resolved as a stem member of the total Athyriaceae using a tip-dating approach with the Fossilized Birth-Death model in a Bayesian framework. Our study suggests that Early Cretaceous fossils previously assigned to Athyrium require taxonomic revision.  相似文献   

3.
Fifteen taxa of the genus Cicer L. growing naturally in Turkey and out-groups were classified by phylogenetic and cladistic analysis. Taxa of the genus Cicer and the out-group taxa belonging to the closest genera Phaseolus L., Vicia L., Lathyrus L. and Ononis L., which are placed in Phaseoleae, Vicieae and Ononideae tribes, respectively, were used in molecular studies in order to derive their phylogenetic relationships. Morphological, palynological and seed characters were used on the basis of 143 traits. The micromorphological characters of seed and pollen grains were revealed by SEM. Lathyrus L. and Vicia L. species were used as out-groups for numerical analysis. Ten specimens were used for the measurements of metric characters related to the morphological structures of the taxa used for statistical analysis via PAUP and NTSYS-pc packages. Phylogenetic relationships between species and populations of the same species growing in different locations and their variations were determined using molecular methods performed on regions of the Inter Simple Sequence Repeat (ISSR). DNA was isolated from the collected samples, using modified CTAB protocols. ISSR was used for phylogenetic fingerprinting. The data were analyzed with NTSYS-pc package. Standardized data were used to generate a dendrogram that revealed the phylogenetic relationships of the taxa. Geographic distribution of the Cicer taxa appears to be closely related to the Anatolian Diagonal. As a result of this study, four new endemic taxa were added and evaluated for the first time.  相似文献   

4.
Alitocoris Sailer, 1950, consists of four valid species described from Central America. In a recent cladistic analysis of Ochlerini, the genus was considered paraphyletic in the Herrichella Distant, 1911, group of taxa. The present study provides a cladistic analysis of the Herrichella clade, using 88 morphological characters and 40 taxa representing 21 genera of Ochlerini, including all known species of Alitocoris plus 16 new species. Outgroups included Eritrachys bituberculata Ruckes, 1959, Phereclus pluto Stål, 1862, and Adoxoplatys comis Breddin, 1903, with the last used for rooting. The cladistic analysis was conducted using TNT under heuristic searches and implied weighting of characters; 11 K‐values calculated for an average character fit ranged from 50 to 90% of a perfectly hierarchical character. The results corroborated the paraphyly of Alitocoris, calling for changes in the classification of the genus with the proposition of three new genera for two, three, and ten species, respectively, that will be described elsewhere. Alitocoris is redescribed and a key for the species is presented. Alitocoris brunneus, Alitocoris maculosus, and Alitocoris parvus are removed from the genus, and the new species Alitocoris grandis sp. nov. , Alitocoris lateralis sp. nov. , and Alitocoris ornatus sp. nov. are described. © 2013 The Linnean Society of London  相似文献   

5.
6.
The phylogeny of the New Zealand hepialid moths was estimated from a cladistic analysis of sixty‐three morphological characters, from all life cycle stages. One hundred and sixteen maximum parsimony trees were produced. The phylogenetic reconstruction indicated that the currently recognized generic concepts, and the four informal lineages hypothesized in a previous morphological taxonomic revision, were monophyletic. The relationships of species within genus Wiseana were not fully resolved. Analysis of a data set of thirty‐nine adult male characters from the New Zealand taxa and the Australian genera Jeana, Oxycanus and Trictena supported the monophyly of the New Zealand ‘Oxycanus’ s.s lineage.  相似文献   

7.
Specimens of the velvety shore bugs (Hemiptera: Ochtheridae) occur in the Early Cretaceous Yixian Formation in north‐eastern China. We describe two new genera and three new species –Pristinochterus ovatus Yao, Zhang & Ren sp. nov., Floricaudus multilocellus Yao, Ren & Shih gen.n. et sp.n. and Angulochterus quatrimaculatus Yao, Zhang & Ren gen.n. et sp.n. – from this deposit. A cladistic analysis based on a combination of fossil and extant taxa, and their morphological characters, clarifies the phylogenetic status of the new fossils and allows the reconstruction of relationships within the family Ochteridae. Two main clades within Ochteridae are recognized from the cladistic analysis: Pristinochterus Yao Cai & Ren and Floricaudus Yao, Ren & Shih gen.n. form a monophyletic lineage; and Angulochterus Yao, Zhang & Ren gen.n. emerges as a sister group to all extant velvety shore bugs. A key to all fossil and extant genera of Ochteridae is provided.  相似文献   

8.
The late Ediacaran siliciclastic successions of eastern Newfoundland, Canada, are renowned for their fossils of soft‐bodied macro‐organisms, which may include some of the earliest animals. Despite the potential importance of such fossils for evolutionary understanding, the taxonomic framework within which Ediacaran macrofossils are described is not clearly defined. Rangeomorphs from a newly discovered fossil surface on the Bonavista Peninsula, Newfoundland, require us to reconsider contemporary use of morphological characters to distinguish between genera and species within Ediacaran taxa. The new surface exhibits remarkable preservational fidelity, resolving features smaller than 0.1 mm in dimension in both frondose and non‐frondose taxa. Such preservation permits the recognition of rarely observed fourth‐ and fifth‐order rangeomorph branching, offering unparalleled opportunities to investigate the fine‐scale construction of rangeomorph taxa including Culmofrons plumosa Laflamme et al., 2012. Our observations enable resolution of taxonomic issues relating to rangeomorphs, specifically overlap between the diagnoses of the frondose genera Beothukis Brasier and Antcliffe, 2009 and Culmofrons. We propose a taxonomic framework for all Ediacaran macrofossils whereby gross architecture, the presence/absence of discrete morphological characters and consideration of growth programme are used to distinguish genera, whereas morphometric or continuous characters define taxa at the species level. On the basis of its morphological characters, Culmofrons plumosa is herein synonymized to a species (Beothukis plumosa comb. nov.) within the genus Beothukis. This discussion emphasizes the need to standardize the taxonomic approach used to describe Ediacaran macrofossil taxa at both the genus and species levels, and raises important considerations for future formulation of higher‐level taxonomic groups.  相似文献   

9.
A cladistic analysis of subtribe, Pleurothallidinae (Orchidaceae) is based on 45 anatomical/ morphological characters. The ingroup members comprise 24 genera; the large genus Pleurothallis consists of two subgenera and ten species complexes. Three taxa representing subtribes Laeliinae and Arpophyllinae are designated as outgroup. Eight most parsimonious trees were discovered using computer assisted software (length = 230; CI = 0.27). The hypothesis that subtribe Pleurothallidinae has undergone a unilinear reduction in the number of pollinia is not supported by this study. Although the eight-pollinia state as represented by Octomeria apparently is plesiomorphic, the two-pollinia and four-pollinia states arose early in the phylogeny of the subtribe. Both two-and four-pollinia states subsequently reappeared as parallelisms. The six-pollinia state exhibited in Brachionidium is autapomorphic. This cladistic analysis suggests that Pleurothallis is not a natural genus and, perhaps may be divided into several discrete genera.  相似文献   

10.
A cladistic analysis of subtribe, Pleurothallidinae (Orchidaceae) is based on 45 anatomical/ morphological characters. The ingroup members comprise 24 genera; the large genus Pkurothallis consists of two subgenera and ten species complexes. Three taxa representing subtribes Laeliinae and ArpophyUinae are designated as outgroup. Eight most parsimonious trees were discovered using computer assisted software (length = 230; CI = 0.27). The hypothesis that subtribe Pleurothallidinae has undergone a unilinear reduction in the number of pollinia is not supported by this study. Although the eight-pollinia state as represented by Octomeria apparently is plesiomorphic, the two-pollinia and four-pollinia states arose early in the phytogeny of the subtribe. Both two-and four-pollinia states subsequently reappeared as parallelisms. The six-pollinia state exhibited in Brachionidium is autapomorphic. This cladistic analysis suggests that Pkurothallis is not a natural genus and, perhaps may be divided into several discrete genera.  相似文献   

11.
Molecular phylogenetic studies of the extant Pantherinae have resulted in a variety of different hypotheses of relationships. This study presents the results of a cladistic study encompassing 45 osteological and dental characters in the skull and mandible, as well as 13 soft‐tissue and behavioural characters. Analyzing extant pantherines with osteological data only resulted in two equally parsimonious trees, which differed only with respects to the jaguar, a taxon which shows morphological affinity to the tiger as well as the lion + leopard. Addition of soft‐tissue characters resolved this ambiguity, and led to markedly improved bootstrap values. The inclusion of fossil taxa did not have an impact on topology, but was important for a correct understanding of character evolution, due to the fossils having a combination of characters unlike those of any extant taxon. The clouded leopard is the most basal pantherine, followed by the snow leopard. The large pantherines are a well supported group, to which the snow leopard does not belong, contrary to some molecular studies. Panthera palaeosinensis is no tiger, but may be close to the stem group from which the tiger evolved. P. atrox and P. spelaea are not on the lion lineage, as traditionally assumed, but are successive outgroups to the lion + leopard, although the position of P. spelaea is tentative, but is supported by other lines of evidence such as brain anatomy. © The Willi Hennig Society 2008.  相似文献   

12.
Thum  Ryan A. 《Hydrobiologia》2004,519(1-3):135-141
The phylogenetic relationships among the numerous genera of diaptomid copepods remain elusive due to difficulties in obtaining sufficient numbers of phylogenetically informative morphological characters for cladistic analysis. Molecular phylogenetic techniques offer high potential to resolve phylogenetic relationships in the absence of sufficient morphological characters because of the ease in which many characters can be unambiguously coded. I present the first molecular phylogeny for diaptomid copepod genera using 18S rDNA. Specifically, I test Light’s (1939) hypothesis regarding the interrelationships among the North American diaptomid genera. The 18S phylogeny is remarkably consistent with Light’s hypothesis. The endemic North American genera represent a monophyletic group exclusive of the non-endemic genera. Moreover, his hypothesized basal genus for the North America genera, Hesperodiaptomus, is the basal genus in this analysis. However, his Leptodiaptomus group is not reciprocally monophyletic with his Hesperodiaptomus group, but is rather a derived member of the latter group. Finally, the genus Mastigodiaptomus is found to be more closely allied with the non-endemic genera, as Light suggested. This phylogeny contributes heavily to the understanding of phylogenetic relationships among North American diaptomids and has large implications for the systematics of diaptomids in general. The use of 18S rDNA sequences in phylogenetic analyses of diaptomid copepods can be used to confirm the monophyly of recognized genera, the interrelationships among genera, and subsequent biogeographic interpretation of the family’s diversification. The use of molecular data, such as 18S rDNA sequences, to test phylogenetic hypotheses based on a very limited number of morphological characters will be a particularly useful approach to phylogenetic analysis in this system.  相似文献   

13.
A cladistic analysis of all known genera in the Carangidae was made mostly on the basis of external and osteological characters. Polarity for each character was determined by outgroup comparison using the echeneoids as the first outgroup and the Nematistiidae as the second. In the Carangini, there were four hypothesized monophyletic groups at the rank of sub-tribe. Parastromateus is the sister group of the remaining twenty-one carangine genera which are divided into three groups. The first group consists of a single genus Megalaspis. The second group is composed of Trachurus, Decapterus, Selar, Atule, Selaroides, Pantolabus, Alepes, Hemicaranx, Pseudocaranx, Kaiwarinus, and Chloroscombrus. The third group comprises Uraspis Caranx, Gnathanodon, Carang ichthys, Carangoides, Atropus, Ulua, Alectis, and Selene.  相似文献   

14.
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   

15.
16.
Adenocaulon andEriachaenium are two problematic genera because their tribal and subfamilial placement in Asteraceae is uncertain. Previous cladistic analyses based on molecular data undertaken to analyze the relationships within Asteraceae, placeAdenocaulon in the tribe Mutisieae (Cichorioideae). This paper investigates cladistic relationships amongAdenocaulon andEriachaenium and tribes of subfamilies Cichorioideae and Asteroideae using morphological data. Thirty-eight characters were scored across 52 genera selected as exemplar taxa to represent the current classification system. In the analysis (one tree, length = 86, c.i. = 0.55, r.i. = 0.64)Adenocaulon andEriachaenium are sister taxa and appear as an isolated clade nested in Cichorioideae. A new, tentative position among the tribes of the paraphyletic Cichorioideae is proposed for these two isolated genera.  相似文献   

17.
18.
Phylogenetic relationships within the bee family Megachilidae are poorly understood. The monophyly of the subfamily Fideliinae is questionable, the relationships among the tribes and subtribes in the subfamily Megachilinae are unknown, and some extant genera cannot be placed with certainty at the tribal level. Using a cladistic analysis of adult external morphological characters, we explore the relationships of the eight tribes and two subtribes currently recognised in Megachilidae. Our dataset included 80% of the extant generic‐level diversity, representatives of all fossil taxa, and was analysed using parsimony. We employed 200 characters and selected 7 outgroups and 72 ingroup species of 60 genera, plus 7 species of 4 extinct genera from Baltic amber. Our analysis shows that Fideliinae and the tribes Anthidiini and Osmiini of Megachilinae are paraphyletic; it supports the monophyly of Megachilinae, including the extinct taxa, and the sister group relationship of Lithurgini to the remaining megachilines. The Sub‐Saharan genus Aspidosmia, a rare group with a mixture of osmiine and anthidiine features, is herein removed from Anthidiini and placed in its own tribe, Aspidosmiini, new tribe . Protolithurgini is the sister of Lithurgini, both placed herein in the subfamily Lithurginae; the other extinct taxa, Glyptapina and Ctenoplectrellina, are more basally related among Megachilinae than Osmiini, near Aspidosmia, and are herein treated at the tribal level. Noteriades, a genus presently in the Osmiini, is herein transferred to the Megachilini. Thus, we recognise four subfamilies (Fideliinae, Pararhophitinae, Lithurginae and Megachilinae) and nine tribes in Megachilidae. We briefly discuss the evolutionary history and biogeography of the family, present alternative classifications, and provide a revised key to the extant tribes of Megachilinae.  相似文献   

19.
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   

20.
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