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1.
The anatomy of the spectacular sabretoothed carnivorans has been studied many times. Their behavioural and biomechanical implications are well known in adults, but not in juvenile individuals, which are poorly represented in the fossil record. This work reports on a newly discovered Hoplophoneini (Nimravidae Nimravinae) of 5–6 months of age, which represents the earliest and one of the most complete juvenile crania discovered. We discuss and compare the juvenile anatomy of Palaeogene nimravids relative to that of other mammals, especially other carnivorans including the Miocene nimravids (i.e. Barbourofelinae). We also discuss the ontogenetic development of this individual and other sabretoothed predators, which provides important data for reconstructing the biology of these extinct predators. Our study of the juvenile anatomy of the Hoplophoneini reveals an original association of basicranial features: the ectotympanic rotates away from the cranium earlier than in other mammals, which may be an additional autapomorphy distinguishing the Palaeogene Nimravidae from other Carnivora; within Palaeogene Nimravidae, at a similar ontogenetic stage, there is a major difference in development and maximum ventral extension of ossification of the caudal entotympanic; in contrast to the Miocene nimravid Barbourofelis, there is no strong relationship between the eruption of the upper canines and the development of other sabretoothed features (especially the mandibular flange) in the individual described. These results confirm the conclusions of recent studies which suggested that Palaeogene Nimravidae (Nimravinae) and Miocene Nimravidae (Barbourofelinae) are not closely related. Muscular reconstruction and biomechanical models also confirmed that juvenile individuals were probably not able to kill or hunt any prey. They may have fed on carcasses, eating muscles by using the incisors, and associated with a pulling or twisting action of neck. © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society, 2003, 138 , 477–493.  相似文献   

2.
Vuji?, A., Ståhls, G., A?anski, J., Bartsch, H., Bygebjerg, R. & Stefanovi?, A. (2013). Systematics of Pipizini and taxonomy of European Pipiza Fallén: molecular and morphological evidence (Diptera, Syrphidae). —Zoologica Scripta, 42, 288–305. In the present work the monophyly and molecular phylogenetic relationships of the genera of tribe Pipizini (Syrphidae) were investigated based on mitochondrial cytochrome c oxidase subunit I (COI) and nuclear 28S rDNA sequences, and the relationships among species of genus Pipiza Fallén, 1810 based on mtDNA COI sequences. Molecular phylogenetic analyses of Pipizini supported Pipiza as monophyletic and as sister group to all other Pipizini, and resolved other Pipizini genera as monophyletic lineages except for genus Heringia Rondani, 1856. To recognize the distinctness and maintain the monophyly the genus Heringia was redefined, generic rank was assigned to Neocnemodon Goffe, 1944 stat. n., and the genus Claussenia Vuji? & Ståhls gen. n., type‐species Claussenia hispanica (Strobl, 1909), was described. A revision of the European Pipiza species, including a discussion of taxonomic characters and a morphological redefinition of all included species, is presented. One new species, Pipiza laurusi Vuji? & Ståhls sp. n. was described. The taxa Pipiza carbonaria Meigen, 1822; Pipiza fasciata, Meigen 1822; Pipiza lugubris (Fabricius, 1775), Pipiza noctiluca (Linneaues, 1758), Pipiza notata Meigen, 1822 were redefined. Lectotypes are designated for 17 taxa, and neotypes were designated for seven taxa. Fourteen new synonymies were proposed. Male genitalia were illustrated for all the species, and a key of the 12 European species for males and females was provided. Geometric morphometrics of wing landmarks and extended sampling of mtDNA COI sequences was employed to delimitate taxa of the P. noctiluca and P. lugubris complexes. Despite subtle morphological differences, wing geometric morphometrics variables of wing size and shape showed highly significant differences among species within P. noctiluca and P. lugubris complexes, which were supported by the molecular data.  相似文献   

3.
The flora of Western Europe is rich in endemic species of Apiaceae, many of which have been poorly investigated and whose phylogenetic relationships are poorly known. To investigate relationships among three endemic European genera (Dethawia, Meum, and Rivasmartinezia gen. nov.) and to ascertain their higher-level phylogenetic placements within the subfamily Apioideae, we examined nuclear ribosomal DNA ITS sequences and the plastid trnL-trnF region. Phylogenies estimated using parsimony and Bayesian inference reveal that (1) the historically known “Conioselinum chinense” Clade (Conioselinum chinense; C. scopulorum; Ligusticum canadense; L. porteri; Meum athamanticum; Mutellina purpurea; and Trochiscanthes nodiflora) comprise a strongly supported monophyletic group (100% BS); (2) the genera Dethawia and Meum comprise a strongly supported monophyletic group also included in the “Conioselinum chinense” Clade; and finally (3) a new genus (Rivasmartinezia) with one species (R. vazquezii) from the Northwestern of the Iberian Peninsula, and placed in the basal position in the “Conioselinum chinense” Clade, is described for the family Apiaceae subfamily Apioideae.  相似文献   

4.
Fossil testudinids are known in Europe since the Eocene, with several taxa of medium size (from more than 0.3 m to less than 0.7 m) recognized in the Palaeogene record, most of them being poorly known. The size of several European Neogene taxa was larger (between 1 and 2 m). These large testudinids were relatively abundant and diverse, ranging from the early Miocene to the Pleistocene. However, there is a nomenclatural gap at the generic level for the Neogene forms, as their generally used assignment to the more primitive Eocene Cheirogaster cannot be sustained. This is because relatively little material has been assigned to the described species, and also because of the absence of a detailed study comparing all of the European taxa. Here, the European Cenozoic taxa are incorporated for the first time in a data matrix, so that a hypothesis on their phylogenetic relationships is justified. This study identified the large testudinids from the Neogene of Europe as belonging to a monophyletic clade, assigned to the new genus T itanochelon . The hitherto poorly understood ‘Testudobolivari, proposed nearly a century ago but lacking diagnosis, is analysed in detail. It is recognized as the best‐represented large testudinid from the European record, and is identified as the type species of T itanochelon gen. nov. Its comparison with the other Neogene species allowed a detailed study of the new genus and an analysis of its phylogenetic relationships with the other European taxa. © 2014 The Linnean Society of London  相似文献   

5.
The phylogenetic relationships within many clades of the Crassulaceae are still uncertain, therefore in this study attention was focused on the “Acre clade”, a group comprised of approximately 526 species in eight genera that include many Asian and Mediterranean species of Sedum and the majority of the American genera (Echeveria, Graptopetalum, Lenophyllum, Pachyphytum, Villadia, and Thompsonella). Parsimony and Bayesian analyses were conducted with 133 species based on nuclear (ETS, ITS) and chloroplast DNA regions (rpS16, matK). Our analyses retrieved four major clades within the Acre clade. Two of these were in a grade and corresponded to Asian species of Sedum, the rest corresponded to a European–Macaronesian group and to an American group. The American group included all taxa that were formerly placed in the Echeverioideae and the majority of the American Sedoideae. Our analyses support the monophyly of three genera – Lenophyllum, Thompsonella, and Pachyphytum; however, the relationships among Echeveria, Sedum and the various segregates of Sedum are largely unresolved. Our analyses represents the first broad phylogenetic framework for Acre clade, but further studies are necessary on the groups poorly represented here, such as the European and Asian species of Sedum and the Central and South American species of Echeveria.  相似文献   

6.
The systematics and taxonomy of North Americancyprinid fishes has historically been said tobe in a chaotic state of affairs. Much of theconfusion as to relationships of species restsin the lack of explicit phylogenetic hypothesesof species and reliance upon degree ofdistinctiveness of taxa or their overallsimilarity for generic placement. Some specieshave had more turbulent or variable taxonomichistories than others. The ornate shiner, Cyprinella ornata, is one of those species,having been placed in the genera Notropis,Codoma, and Cyprinella within the last20 years and found in current texts in any ofthese three genera. Most of the confusionregarding placement of this species has beenrelated to lack of explicit phylogenetichypotheses to formulate its classification, butto a certain degree some researchers haveignored phylogenetic studies and preferred torely upon its morphological distinctiveness orreproductive behavioral traits of questionablehomology to place it in a monotypic genus andalign it with the genera Pimephales andOpsopoeodus.I present a phylogenetic analysis based oncomplete Cytochrome b sequences fromornate shiners, other species of Cyprinella, purported relatives, and severalother species of the Shiner Clade to determinethe phylogenetic affinities of this enigmaticspecies. Molecular analysis reveals the ornateshiner to be more closely related to species ofCyprinella than to a Pimephalesplus Opsopoeodus clade as previouslydiscussed in one morphological analysis, or asargued by Page and Johnston (1990), Johnstonand Page (1992) and Page and Ceas (1989) basedon observations of spawning behaviors andhypotheses of homology between crevice-spawningand egg-clumping behaviors. This molecularanalysis is more consistent with earliermorphological phylogenetic hypotheses of Mayden(1989) wherein these two clades are notconsidered to be closely related and the ornateshiner is a member of the genus Cyprinella.  相似文献   

7.
Xanthopygina is a group of colourful, neotropical rove beetles (Staphylinidae) comprising 28 genera and more than 350 species. While many genera are found on rotting fruits, carrion, dung and mushrooms, several taxa have evolved associations with social insects. Previous phylogenetic analyses have used only a subset of genera and were based solely on molecular data. In this paper, we performed Bayesian and maximum likelihood phylogenetic analyses of all known genera, including three potentially new genera, based on molecular (4,797 bp) and morphological (91) characters. Our results reaffirmed the monophyly of the subtribe and divided it into eight major lineages: the Elmas, Gastrisus, Isanopus, Ocyolinus, Plociopterus, Smilax, Trigonopselaphus and Xanthopygus groups. We hypothesized that myrmecophily evolved once in the common ancestor of the Smilax group, and that sphecophily possibly evolved twice, in the Trigonopselaphus and Xanthopygus groups.  相似文献   

8.
Traditional concepts of Collybia (Agaricales) have included a variety of morphologically disparate taxa. Reapplication of some characters used in circumscribing Collybia s.l. suggests realignment of well-known North American and European species into three genera, viz. Collybia s.s, Rhodocollybia, and Gymnopus. Rhodocollybia is recognized here at generic rank based on morphological characteristics and phylogenetic signaling. Seven new species epithets under Rhodocollybia, and a new combination under Gymnopus, are proposed. A key to species of Rhodocollybia found in neotropical montane forests is provided.  相似文献   

9.
Aim To discover the pattern of relationships of areas of endemism for Australian genera in the plant family Rhamnaceae tribe Pomaderreae for comparison with other taxa and interpretation of biogeographical history. Location Australian mainland, Tasmania and New Zealand. Methods A molecular phylogeny and geographic distribution of species within four clades of Pomaderreae are used as a basis for recognition of areas of endemism and analysis of area relationships using paralogy‐free subtrees. The taxon phylogeny is the strict consensus tree from a parsimony analysis of 54 taxa, in four clades, and sequence data for the internal transcribed spacer regions of ribosomal DNA (ITS1‐5.8S‐ITS2) and the plastid DNA region trnL‐F. Results The biogeographical analysis identified five subtrees, which, after parsimony analysis, resulted in a minimal tree with 100% consistency and seven resolved nodes. Three sets of area relationships were identified: the areas of Arnhem and Kimberley in tropical north Australia are related based on the phylogeny of taxa within Cryptandra; the moister South‐west of Western Australia, its sister area the coastal Geraldton Sandplains, the semi‐arid Interzone region and arid Western Desert are related, based on taxa within Cryptandra, Spyridium, Trymalium and Pomaderris; and the eastern regions of Queensland, McPherson‐Macleay, south‐eastern New South Wales (NSW), Victoria, southern Australia, Tasmania and New Zealand are related based on Cryptandra, Pomaderris and Spyridium. Tasmania and NSW are related based entirely on Cryptandra, but the position of New Zealand relative to the other south‐eastern Australian regions is unresolved. Main conclusions The method of paralogy‐free subtrees identified a general pattern of geographic area relationships based on Australian Pomaderreae. The widespread distribution of clades, the high level of endemicity and the age of fossils for the family, suggest that the Pomaderreae are an old group among the Australian flora. Their biogeographical history may date to the early Palaeogene with subsequent changes through to the Pleistocene.  相似文献   

10.
Cladistic analyses of 17 wild and cultivated pea taxa were performed using morphological characters, and allozyme and RAPD (random amplified polymorphic DNA) markers. Both branch-and-bound and bootstrap searches produced cladograms that confirmed the close relationships among the wild species and cultivars of Pisum proposed by a variety of systematic studies. Intraspecific rankings were supported for northern P. humile, southern P. humile, P. elatius and P. sativum, which together comprise a single-species complex. P. fulvum, while clearly the most divergent of the pea taxa, could also be assigned to the same species complex without violating the hierarchial logic of the cladogram. Its inclusion or exclusion depends on whether the level of interfertility it displays with other pea taxa or its overall morphological and chromosomal distinction are emphasized. As suggested by previous studies, northern P. humile was the most likely sister taxon to cultivated P. sativum; although, rigorous phylogenetic evaluation revealed a close genealogical affinity among P. elatius, northern P. humile and P. sativum. Despite their limited number, the 16 morphological characters and allozyme markers used precisely organized the pea taxa into established taxonomic groupings, perhaps in part reflecting the role morphology has played historically in pea classification. The RAPD data also generally supported these same groupings and provided additional information regarding the relationships among the taxa. Given that RAPDs are relatively quick and easy to use, are refractory to many environmental influences, can be generated in large numbers, and can complement traditional characters that may be limited in availability, they provide a valuable new resource for phylogenetic studies.  相似文献   

11.
Phylogenetic relationships of the subfamily Combretoideae (Combretaceae) were studied based on DNA sequences of nuclear ribosomal internal transcribed spacer (ITS) regions, the plastid rbcL gene and the intergenic spacer between the psaA and ycf3 genes (PY-IGS), including 16 species of eight genera within two traditional tribes of Combretoideae, and two species of the subfamily Strephonematoideae of Combretaceae as outgroups. Phylogenetic trees based on the three data sets (ITS, rbcL, and PY-IGS) were generated by using maximum parsimony (MP) and maximum likelihood (ML) analyses. Partition-homogeneity tests indicated that the three data sets and the combined data set are homogeneous. In the combined phylogenetic trees, all ingroup taxa are divided into two main clades, which correspond to the two tribes Laguncularieae and Combreteae. In the Laguncularieae clade, two mangrove genera, Lumnitzera and Laguncularia, are shown to be sister taxa. In the tribe Combreteae, two major clades can be classified: one includes three genera Quisqualis, Combretum and Calycopteris, within which the monophyly of the tribe Combreteae sensu Engler and Diels including Quisqualis and Combretum is strongly supported, and this monophyly is then sister to the monotypic genus Calycopteris; another major clade includes three genera Anogeissus, Terminalia and Conocarpus. There is no support for the monophyly of Terminalia as it forms a polytomy with Anogeissus. This clade is sister to Conocarpus. Electronic Publication  相似文献   

12.
Small-subunit ribosomal DNA (SSU) sequences for 14 members of the rhodophyte order Acrochaetiales were used to generate phylogenetic trees to determine whether the Acrochaetiales is monophyletic and to assess the relationships of acrochaetioid algae to closely related taxa. Within the Acrochaetiales, two strongly supported groups are recognized: one group that includes, in addition to three other species, the type species of the genera Acrochaetium, Audouinella and Rhodochorton; and a second group that includes an unequivocal representative of Colaconema and nine additional species. The relationships of these groups with the Batrachospermales, Palmariales and Nemaliales were not resolved and the possibility that the Acrochaetiales is polyphyletic was not eliminated. Resolution of relationships for species within these groups was strong in only a few cases, with many of the phylogenetic issues at this level remaining equivocal. Our results do not position Camontagnea in the Acrochaetiales, as has recently been suggested, but strongly ally this genus to the family Rhodothamniellaceae of the Palmariales. The phylogenetic position of Rhododraparnaldia, an alga intermediate between the Acrochaetiales and Batrachospermales, remains unresolved. These molecular results provide a foundation for assessing the taxonomic significance of phenotypic characters (e.g. anatomy, life histories, morphology, phycoerythrin type and plastid details) variously considered taxonomically significant in the Acrochaetiales.  相似文献   

13.
Abstract. The subfamily Ambleminae is the most diverse subfamily of fresh‐water mussels (order Unionoida), a globally diverse and ecologically prominent group of bivalves. About 250 amblemine species occur in North America; however, this diversity is highly imperiled, with the majority of species at risk. Assessing and protecting this diversity has been hampered by the uncertain systematics of this group. This study sought to provide an improved phylogenetic framework for the Ambleminae. Currently, 37 North American genera are recognized in Ambleminae. Previous phylogenetic studies of amblemines highlighted the need for more extensive sampling due to the uncertainties arising from polyphyly of many currently recognized taxa. The present study incorporated all amblemine genera occurring in North America north of the Rio Grande, with multiple species of most genera, including the type species for all but seven genera. A total of 192 new DNA sequences were obtained for three mitochondrial gene regions: COI, 16S, and ND1. In combination with published data, this produced a data matrix incorporating 357 gene sequences for 143 operational taxonomic units, representing 107 currently recognized species. Inclusion of published data provides additional taxa and a summary of present molecular evidence on amblemine phylogeny, if at the cost of increasing the amount of missing data. Parsimony and Bayesian analyses suggest that most amblemine genera, as currently defined, are polyphyletic. At higher taxonomic levels, the tribes Quadrulini, Lampsilini, and Pleurobemini were supported; the extent of Amblemini and the relationships of some genera previously assigned to that tribe remain unclear. The eastern North American amblemines appear monophyletic. Gonidea and some Eurasian taxa place as probable sister taxa for the eastern North American Ambleminae. The results also highlight problematic taxa of particular interest for further work.  相似文献   

14.
Planorbid gastropods are the most diverse group of limnic pulmonates, with both discoidal and highspired taxa. Phylogenetic relationships among these genera are confused and controversial. In particular, the monophyly of the limpet‐like taxa (traditionally Ancylidae) is disputed. Even recent molecular studies have concluded that substantially more work is necessary to solve the remaining issues concerning intergeneric phylogenetic relationships and higher taxa systematics. Planorbid snails are of great significance for humans as several members of this group are intermediate hosts of blood flukes (schistosomes) causing a chronic disease, schistosomiasis. We used the two independent molecular markers COI and 18S (concatenated dataset of 2837 nucleotide bp) to infer phylogenetic relationships of 26 genera (27 species) of Planorboidea, represented mostly by type species from mainly topotypical populations. With the majority of the taxa discussed not having been studied previously, this study attempted to test several hypotheses on planorbid phylogenetic relationships using Bayesian inference techniques. The monophyly of Planorboidea (= ‘Ancyloplanorbidae’) is strongly suggested on the basis of our extensive molecular analysis. Besides a distinct Burnupia clade, two major clades were recovered that correspond to family level taxa (traditional Bulinidae and Planorbidae). Considerable rearrangements of suprageneric taxa are evident from the phylogeny inferred. Therefore, the only clades recognized by current classifications and supported by our analysis are Planorbini and Segmentinini. The present study found that Ancylidae as traditionally understood, i.e. covering most freshwater limpet gastropods, is paraphyletic, as the genera of Burnupia and Protancylus have been shown to lie phylogenetically outside the Ancylini. Chromosome numbers and levels of polyploidy are discussed in the light of the new phylogeny. An earlier theory of shell shape evolution, i.e. that of patelliform taxa being most advanced, was not supported by this study; a limpet‐shaped taxon is most basal within Planorboidea. Although many taxa still remain to be studied, our results will hopefully contribute towards a better understanding of this very important group of freshwater organisms. Some taxonomic implications are discussed.  相似文献   

15.
16.
Fabre, P.‐H., Galewski, T., Tilak, M.‐k. & Douzery, E.J.P. (2012) Diversification of South American spiny rats (Echimyidae): a multigene phylogenetic approach. —Zoologica Scripta, 00, 000–000. We investigated the phylogenetic relationships of 14 Echimyidae (spiny rats), one Myocastoridae (nutrias) and one Capromyidae (hutias) genera based on three newly sequenced nuclear genes (APOB, GHR and RBP3) and five previously published markers (the nuclear RAG1 and vWF, and the mitochondrial cytochrome b, 12S rRNA and 16S rRNA). We recovered a well‐supported phylogeny within the Echimyidae, although the evolutionary relationships among arboreal echimyid taxa remain unresolved. Molecular divergence times estimated using a Bayesian relaxed molecular clock suggest a Middle Miocene origin for most of the extant echimyid genera. Echimyidae seems to constitute an example of evolutionary radiation with high species diversity, yet they exhibit only narrow skull morphological changes, and the arboreal and terrestrial taxa are shown to retain numerous plesiomorphic features. The most recent common ancestor of spiny rats is inferred to be a ground‐dwelling taxon that has subsequently diverged into fossorial, semiaquatic and arboreal habitats. The arboreal clade polytomy and ancestral character estimations suggest that the colonization of the arboreal niche constituted the keystone event of the echimyid radiation. However, biogeographical patterns suggest a strong influence of allopatric speciation in addition to ecology‐driven diversification among South American spiny rats.  相似文献   

17.
Aim We reconstructed the phylogeny of the lichen genus Nephroma (Peltigerales) to assess the relationships of species endemic to Macaronesia. We estimated dates of divergences to test the hypothesis that the species arose in Macaronesia (neo‐endemism) versus the oceanic archipelagos serving as refugia for formerly widespread taxa (palaeo‐endemism). Location Cosmopolitan with a special focus on the archipelagos of the Azores, Madeira and the Canary Islands. Methods DNA sequences were obtained from 18 species for three loci and analysed using maximum parsimony, maximum likelihood and Bayesian inferences. Divergence dates were estimated for the internal transcribed spacer (ITS)‐based phylogeny using a relaxed molecular clock. Reconstruction of the ancestral geographical range was conducted using the Bayesian 50% majority rule consensus tree under a parsimony method. Results The backbone phylogenetic tree was fully supported, with Nephroma plumbeum as sister to all other species. Four strongly supported clades were detected: the Nephroma helveticum, the N. bellum, the N. laevigatum and the N. parile clades. The latter two share a common ancestor and each includes a widespread Holarctic species (N. laevigatum and N. parile, respectively) and all species endemic to Macaronesia. The data suggest a neo‐endemic origin of Macaronesian taxa, a recent range expansion from Macaronesia of both widespread species, a range expansion limited to the Mediteranean Basin and south‐western Europe for another taxon, and a long dispersal event that resulted in a speciation event in the western parts of North America. Main conclusions The Macaronesian endemic species belong to two sister clades and originated from a most recent common ancestor (MRCA) shared with one widely distributed taxon, either N. parile or N. laevigatum. Estimates of the mean divergence dates suggest that the endemics originated in the archipelagos after the rise of the volcanic islands, along with the ancestor to the now widespread species, which probably expanded their range beyond Macaronesia via long‐distance dispersal. This study provides the first phylogenetic evidence of Macaronesian neo‐endemism in lichenized fungi and provides support for the hypothesis that oceanic islands may serve as a source for the colonization of continents. However, further data are needed to properly assess the alternative hypothesis, namely colonization from western North America.  相似文献   

18.
Enzyme electrophoresis was employed to ascertain the number of loci encoding plastid phosphoglucose isomerase (PGI) in species representing all sections of North American Coreopsis. Several species from each of the closely related genera Bidens, Coreocarpus, Cosmos, and Thelesperma were also examined. Species in nine of the 11 sections of North American Coreopsis have two isozymes for plastid PGI, and nearly all species examined in the four other genera also have two (one species has three) isozymes. Since most diploid vascular plants have one plastid PGI isozyme, a gene duplication probably occurred in an ancestor that is common to Coreopsis and the other four genera. That is, two isozymes represent the ancestral number for Coreopsis. The two sections (Electra and Anathysana) apparently lacking the duplication are closely related woody plants restricted largely to Mexico. One gene encoding plastid PGI ostensibly was silenced in a common ancestor of these two sections. This is concordant with other data suggesting a close relationship between the two sections, i.e., they appear to represent a monophyletic group. The electrophoretic data also indicate that 1) the enigmatic monotypic section Silphidium is more closely related to eastern North American sections and not derived from section Electra; and 2) section Anathysana is not ancestral to the three California sections Leptosyne, Pugiopappus, and Tuckermannia; rather, it represents a terminal element closely related to and possibly derived from section Electra.  相似文献   

19.
JULIEN DENAYER 《Palaeontology》2011,54(6):1435-1454
Abstract: A rich and diverse coral fauna collected from the Livian (Viséan, Mississippian) of Zonguldak and Bart?n (North‐western Turkey) contains numerous specimens of Dorlodotia and related forms. The most common species, D. delepinei Charles, 1933 , is redetermined as Dorlodotia briarti, an European species. A new species of Dorlodotia is described for very large, phaceloid forms: D. euxinensis. The genus Ceriodotia is created for species close to Dorlodotia with a cerioid habit. It comprises two species: C. bartinensis and C. petalaxoides, both common in the Viséan of Zonguldak and Bart?n. Based on comparison of morphological characters and features of the astogeny, a phylogenetic lineage is proposed for Dorlodotia and the new taxa. The evolution of D. euxinensis from D. briarti is peramorphic. Subsequent paedomorphosis resulted in the lineage D. euxinensisC. bartinensisC. petalaxoides. Ceriodotia probably includes Viséan taxa from Asia previously described as ‘Acrocyathus’.  相似文献   

20.
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   

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