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1.
A new genus and species of osteoglossomorph fish is described from the Eocene Mahenge site in north central Tanzania. The new species is sympatric with the previously described osteoglossomorph † Singida jacksonoides , but is easily distinguished from it by the presence in the new species of teeth on the jaws and entopterygoid. The new species shares characters with the Heterotidinae, such as the two arms of the preopercle being of similar length and the posterior end of the maxilla lying on the dentary, and other characters with the Osteoglossinae (including † Phareodus ), for example the enlarged pectoral fin ray and the shape of the opercular bone. New specimens of † S. jacksonoides also have been recovered from the site, providing more information on the osteology of this fish. The relationships of these two Mahenge osteoglossomorphs are assessed, with both fishes placed within the Osteoglossidae, but of uncertain position in the family. Addition of the new species to previous cladistic data sets, and the revised information for † S. jacksonoides , causes the subfamily Osteoglossinae to be nonmonophyletic.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 144 , 213–228.  相似文献   

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3.
Caninae is one of the most studied mammalian groups, nevertheless there are relatively few comparative studies on their neuroanatomy. This work contributes to a better knowledge of this subfamily, since it describes the external cerebrum anatomy of 29 out of the 35 living Caninae species, 11 of which are described for the first time. Information about their frontal region appears to be a welcome supplement to the study of the phylogeny. Two distinctive features are recognized, that can be traced back in the fossil record: the sulcal pattern medial to the coronal sulci, and the shape and relative size of the proreal gyrus. Four types are described for the first feature: (1) orthogonal: Canis, Lycaon, Cuon, Atelocynus, Speothos , (2) pentagonal: Vulpes, Alopex, Otocyon, † Eucyon , (3) parenthesis-like: † Dusicyon, Pseudalopex, Chrysocyon , (4) heart-shaped: Urocyon, Cerdocyon, Pseudalopex culpaeus, Nyctereutes . Three types are described for the second feature: (1) elongated and bilaterally compressed: Canis, Cuon, Lycaon, Atelocynus, Speothos, Cerdocyon, † Dusicyon, Chrysocyon, Pseudalopex , † Nyctereutes sinensis , † N. tingi , (2) small: Vulpes, Otocyon, Urocyon, Alopex , (3) wide and low: Nyctereutes procyonoides. On the basis of these features some phylogenetic interpretations are presented: the fossil Asian Nyctereutes is close to Cerdocyon, Speothos is close to Atelocynus , Chrysocyon is not related to Canis , Urocyon differs from Vulpes and Pseudalopex culpaeus differs from the rest of the Pseudalopex species.  © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society , 2003, 138 , 505–522.  相似文献   

4.
The phylogenetic relationships of the fossil orussid taxa Mesorussus taimyrensis and Minyorussus luzzi are examined by analysing them together with a large data set compiled previously for the extant Orussidae. The fossils are placed in an unresolved trichotomy with the extant Orussidae. The phylogeny is used for evaluating the hypothesis that the ancestors of the family had reduced body size; the results of this analysis are inconclusive. The biogeographical history of the Orussidae is explored. The common ancestor of the family was probably widespread, the initial splitting events taking place prior to or coinciding with the separation of Laurasia from Gondwana. Later putative vicariance events can be correlated with the gradual breakup of Gondwana. However, the biogeographical history of the Orussidae is dominated by speciation within regions and dispersal. The minimum age of the common ancestor of the Orussidae is >180 Myr when estimated from the biogeographical pattern, >95 Myr when estimated from the phylogenetic position of the fossils; the earlier date is considered to be the most likely.  © 2004 The Linnean Society of London , Biological Journal of the Linnean Society , 2004, 82 , 139–160.  相似文献   

5.
The taxonomic affinity of Halosphaeria cucullata to Halosphaeria is reassessed based on a recent collection of this fungus. Halosphaeria cucullata is characterized by immersed, darkly coloured ascomata, clavate asci which deliquesce very early in development, and cylindrical ascospores with or without a polar cap-like appendage at one end. In a phylogenetic analysis of the LSU rDNA sequences from members of the Halosphaeriaceae, H. cucullata did not form a monophyletic clade with H. appendiculata , the type species of the genus. These results suggest that H. cucullata should not be included in Halosphaeria . Okeanomyces gen. nov. is proposed to accommodate this fungus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 223–229.  相似文献   

6.
Recent molecular analyses have demonstrated that the traditional Lucinoidea, comprising the extant families Lucinidae, Thyasiridae, Ungulinidae, Fimbriidae, and Cyrenoididae, is not monophyletic. Thyasiridae and Ungulinidae are unrelated to Lucinidae, a result corroborated by clear morphological differences between the groups. Chemosymbiosis in Thyasiridae and Lucinidae has been independently derived. Within the family Lucinidae, previous ideas of relationship and subfamilial divisions based on shell characters have little support from molecular results. Anatomical characters of the ctenidia, mantle gills, and posterior apertures have potential in phylogenetic analysis but rigorous analysis of shell characters is also needed. Although there is a good fossil record of Lucinidae throughout the Cenozoic and Mesozoic, in the Palaeozoic fossils are less frequent and most need reappraisal. The Silurian Ilionia prisca is probably the earliest fossil with convincing lucinid features, followed in the Devonian by Phenacocyclas and some Paracyclas species.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 421–438.  相似文献   

7.
A cladistic analysis that includes representatives of all recent genera of mysticetes and several fossil species that were previously referred to the family Cetotheriidae, with tooth-bearing mysticetes and an archaeocete as an outgroup, is presented here. The result of this analysis forms the base of a revised classification of Mysticeti. Cetotheriidae is redefined as a monophyletic family, which includes the genera Cetotherium , Piscobalaena , and a new subfamily Herpetocetinae, including Herpetocetus , Nannocetus , Metopocetus , and Cephalotropis . Eschrichtiidae is the closest sister taxon to Cetotheriidae. A few species are referred to Eomysticetoidea, whereas the remaining species that were previously referred to Cetotheriidae appear in four clades that branch off from the lineage leading to Balaenopteridae. These are a Mauicetus clade and three clades that are named as new families Aglaocetidae, Pelocetidae, and Diorocetidae.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 875–894.  相似文献   

8.
Relationships among extant and fossil echimyids (Rodentia: Hystricognathi)   总被引:1,自引:0,他引:1  
The echimyid rodents are the most diverse group of Neotropical hystricognaths, with approximately 40 extant and fossil genera. Craniodental characters are proposed in order to formulate hypotheses of phylogenetic relationships within the Echimyidae. A data matrix of 54 taxa and 50 characters is constructed and submitted to parsimony analyses using PAUP and WinClada programs. Analysis of the complete data set results in 47 448 most parsimonious trees 107 steps long. These trees are summarized in a strict consensus tree, which is taken as the main phylogenetic hypothesis resulting from this study. The monophyly of several currently recognized supraspecific taxa is not corroborated. These are: the subfamilies Eumysopinae, Echimyinae, Myocastorinae and Adelphomyinae; and the genera Proechimys , Echimys and Makalata . Conversely, the monophyly of Dactylomyinae and Trinomys is supported. New associations are proposed: (1) a clade comprising the extant Carterodon , Clyomys and Euryzygomatomys and the fossil Pampamys and Theridomysops placed at the base of the crown-group Echimyidae; (2) a clade uniting Proechimys , Hoplomys and Trinomys , which is the sister-taxon of (3) a clade including Mesomys , Lonchothrix , Myocastor and a clade with extant dactylomyines and echimyines and associated fossil taxa. Based on this phylogenetic hypothesis, patterns of tooth evolution in Echimyidae are discussed, and minimum ages for the divergence events within the family are estimated.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 445–477.  相似文献   

9.
The pattern, timing and extent of the evolutionary radiation of anatomically modern birds (Neornithes) remains contentious: dramatically different timescales for this major event in vertebrate evolution have been recovered by the 'clock-like' modelling of molecular sequence data and from evidence extracted from the known fossil record. Because current synthesis would lead us to believe that fossil and nonfossil evidence conflict with regard to the neornithine timescale, especially at its base, it is high time that available data are reconciled to determine more exactly the evolutionary radiation of modern birds. In this review we highlight current understanding of the early fossil history of Neornithes in conjunction with available phylogenetic resolution for the major extant clades, as well as recent advancements in genetic methods that have constrained time estimates for major evolutionary divergences. Although the use of molecular approaches for timing the radiation of Neornithes is emphasized, the tenet of this review remains the fossil record of the major neornithine subdivisions and better-preserved taxa. Fossils allowing clear phylogenetic constraint of taxa are central to future work in the production of accurate molecular calibrations of the neornithine evolutionary timescale.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 153–177.  相似文献   

10.
Most of the estimated 70–80 species of New Zealand Gnaphalieae are endemic. Those of Anaphalioides , Ewartia , Helichrysum , Leucogenes , Rachelia and Raoulia belong to a putatively monophyletic group which is supported by analysis of nuclear ITS DNA sequences and is virtually confined to New Zealand. All species of Craspedia , Euchiton , Ozothamnus and Pseudognaphalium are excluded from this group. A phylogenetic analysis of 42 species of Gnaphalieae, using 57 morphological, anatomical and palynological characters, was conducted to test the monophyly of this group and to seek evidence of generic relationships. The analysis does not resolve basal relationships among the Gnaphalieae studied here. The putative monophyletic New Zealand group is not retrieved. Monophyly is supported for each of Euchiton , Leucogenes , the whipcord species of Helichrysum , the pulvinate species of Raoulia , and Raoulia subg. Raoulia (excluding the aberrant R. cinerea ), but not for Anaphalioides or Raoulia s.l. There are these two distinct groups in Raoulia s.l. but also a substantial number of isolated species. The sole New Zealand species of Ewartia is not a sister species to Australian Ewartia . The Australian species Ewartia planchonii is the sister species to Euchiton rather than to the other Australian species of Ewartia .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 183–203.  相似文献   

11.
The overall most parsimonious hypothesis of relationships based on 200 characters indicates that the Alestidae is the closest relative of Chalceus , a genus previously assigned to the Neotropical Characidae. Chalceus is shifted into the Alestidae, which becomes the only trans-Atlantic family level group within the Characiformes. Various previously proposed suprageneric assemblages within the Alestidae (e.g. Petersiini) failed to delimit monophyletic groups under the intrafamilial phylogenetic analysis. The evaluation of fossil alestids within the context of the phylogeny indicates that the ancestors of Alestes , Arnoldichthys , Brycinus , Bryconaethiops and Hydrocynus evolved prior to the early Eocene (Cuisian of Upper Ypresian), 49–54.8 million years ago, with the fossil Alestoides most closely related to Alestes. The phylogenetic information further indicates a minimum age of 90–112 million years for the Alestidae. Contrary to previous hypotheses, the fossil African Sindacharax was found to be most similar to the clade including the alestid genus Bryconaethiops rather than most closely related to the South American subfamily Serrasalminae. Evaluation of the fossil Mahengecharax carrolli fails to support its hypothesized placement as the sister group to all Recent members of the Alestidae. Two separate episodes of miniaturization and one episode of gigantism occurred within the evolution of the Alestidae.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 1−144. No claim to original US government works.  相似文献   

12.
Abstract:  A taxonomic revision of mackerel-like fishes (Scombridae, Scombroidei, Perciformes) from the Monte Bolca localities in Italy is presented as part of continuing research into phylogenetic relationships of fossil and Recent scombroids. Three new genera are proposed: † Godsilia , † Pseudauxides and † Thunnoscomberoides . In addition, species generally known as † Thynnus bolcensis , † Thynnus lanceolatus , † Scombrosarda propterygia , † Scomberomorus speciosus and † Scomberomorus tenuis are renamed † Thunnoscomberoides bolcensis comb. nov., † Godsilia lanceolata comb. nov., † Auxides propterygius comb. nov. and † Pseudauxides speciosus comb. nov., respectively. † S. tenuis , a nomen nudum , is a junior synonym of † P. speciosus . Provisional phylogenetic hypotheses of these Monte Bolca scombrids are as follows. † Auxides and † Pseudauxides are most likely primitive sister taxa of the mackerels Scomber and Rastrelliger with † Pseudauxides as the most primitive. † Godsilia may be placed between Scombrinae and Scomberomorinae. † Thunnoscomberoides seems to fit between Scombrinae and Thunnini.  相似文献   

13.
We describe Centrolene bacatum , C. buckleyi , Cochranella posadae , and a new species of Cochranella from Yanayacu Biological Station on the Amazonian slopes of the Ecuadorian Andes. The new species differs from other species in Centrolenidae by a combination of characters, including reduced webbing between Fingers III and IV, and kidneys covered with white peritoneum. We summarize the current generic and infrageneric classification in Centrolenidae and discuss some of its problems. A phylogenetic analysis of morphological and behavioural data shows that the genera Centrolene and Cochranella might not be monophyletic; the genus Hyalinobatrachium and, in particular, the group H. fleischmanni seem to be monophyletic. However, an analysis with many more characters is needed to resolve the relationships of glass frogs.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 489–513.  相似文献   

14.
Doradidae is a putatively monophyletic group of South American freshwater catfishes containing 30 extant genera and 72 valid species. Only one study to date has attempted to estimate phylogenetic relationships among doradids. This morphological analysis partitioned species into two basal genera ( Wertheimeria and Francisodoras ) and a crown group of three subfamilies (Platydoradinae, Astrodoradinae and Doradinae) whose relationships were unresolved. No subsequent work has been done to resolve the subfamilial trichotomy or to assess whether postulated intergeneric relationships are accurate. We address this problem with complete sequences (2.5 kilobases, kb) of mitochondrial 12S and 16S rRNA genes and partial (1.3 kb) sequences of the nuclear elongation factor-1 alpha (EF1α) gene from representatives of 23 doradid genera (43 species) and 13 outgroups from additional siluriform families. Phylogenetic analysis of these data yields strong support for the monophyly of Doradidae and Astrodoradinae (as well as other relationships), but otherwise shows significant conflict with morphological results. A partial re-examination of published morphological data indicates that many characters may have been incorrectly polarized and many taxa have incorrect state assignments. Our results provide a framework for ongoing efforts to describe the species-level diversity of this poorly understood neotropical family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 551–575.  相似文献   

15.
Because of the poor state of knowledge of many of the gymnophthalmid genera, systematic revision is necessary to render the classification consistent with evolutionary history. To that end, I conducted a review of the species of three genera of the Cercosaurinae which appear to form a monophyletic group: Cercosaura , Pantodactylus , and Prionodactylus . Phylogenetic analysis of 61 morphological characters was conducted after specimens of all species were examined to evaluate the composition of each taxon. The phylogenetic reconstruction suggested that the genus Prionodactylus was paraphyletic. A new phylogenetic classification is proposed that synonymizes Pantodactylus and Prionodactylus with Cercosaura. Cercosaura is redefined to include 11 species and seven subspecies. A key is provided to distinguish among species.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 137 , 101−115.  相似文献   

16.
We present phylogenetic analyses of the lizard genus Diplodactylus subgenus Strophurus using 1646 aligned positions of mitochondrial DNA sequences containing 893 parsimony-informative characters for samples of 12 species of Strophurus and 19 additional Australian gecko species. Sequences from three protein-coding genes (ND1, ND2 and COI) and eight intervening transfer RNA genes were examined using parsimony, maximum-likelihood and Bayesian analyses. Species of Strophurus appeared to form a monophyletic group with the possible exception of S. taenicauda . Strophurus has evolved two distinct defence/display characteristics: caudal glands, which expel an unpalatable substance, and striking mouth colours. Caudal glands appeared to have arisen once in a common ancestor of Strophurus , with dermal augmentation of caudal glands characterizing a subclade within the subgenus. Evolution of yellow and dark-blue mouth colours in Strophurus occurred in the context of diurnal activity and may be interpreted as an augmentation of defensive behavioural displays. Molecular divergence suggests that arboreality evolved in a common ancestor of Oedura and Strophurus approximately 29 Mya and that the caudal glands of Strophurus arose approximately 25 Mya.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 123–138.  相似文献   

17.
We describe a new trirachodontid cynodont from the base of the Burgersdorp Formation (Subzone A fauna of the Cynognathus Assemblage Zone), of the South African Karoo Basin. Langbergia modisei gen. et sp. nov. is characterized by circular to ovoid in outline upper postcanines and the absence of a maxillary platform lateral to the postcanine series. Apart from the new taxon, we recognize two other species of this family in the Cynognathus Assemblage Zone: Trirachodon berryi and Cricodon metabolus , the latter also represented in the Tanzanian Manda Formation. A phylogenetic analysis of gomphodont cynodonts was conducted using a data matrix of 43 craniodental characters and 18 terminals. Trirachodontidae appears as a monophyletic assemblage, with Langbergia appearing as the sister taxon of Cricodon . The monophyly of trirachodontids is weakly supported, however, with one extra step breaking it. Traversodontid cynodont relationships were also inspected and compared with a recent phylogeny proposed for this group. Considering the resulting phylogeny and the sudden appearance and diversification of Cynognathia representatives, the origin of basal Cynognathia (i.e. Cynognathus , Diademodon , and trirachodontids) is suggested to predate their first appearance in the fossil record.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 383–413.  相似文献   

18.
The systematics of Malagasy Myristicaceae is revised to take into account new collections made since the work by Capuron in the 1970s, as well as improved knowledge from fieldwork and two scanning electron microscopy studies by the author. Four new species are described: Mauloutchia annickiae Sauquet, M. capuronii Sauquet, M. echinocarpa Capuron ex Sauquet, and M. sambiranensis (Capuron) Sauquet. In addition, basic information is given for each remaining Malagasy species of the family (synonymy, type specimen, updated distribution and main distinctive features). According to this treatment, Malagasy Myristicaceae now consist of four endemic genera and 15 species: Brochoneura Warb. (three species), Doyleanthus Sauquet (one species), Haematodendron Capuron (one species) and Mauloutchia (Baill.) Warb. (ten species). Two identification keys to these species are provided: one based primarily on fruit characters and one based primarily on male flower and inflorescence characters. Putative phylogenetic relationships among these species are also indicated, based on a previous combined morphological and molecular study by the author.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 351–368.  相似文献   

19.
This paper represents the first cladistic analysis of the interrelationships of all nominal fossil and living gonorynchiform genera. Gonorynchiformes is the basal group of the superorder Ostariophysi, and is confirmed as monophyletic on the basis of 12 synapomorphies. The Gonorynchiformes is be subdivided into two monophyletic suborders, Chanoidei and Gonorynchoidei. The Chanoidei includes the family Chanidae, which in turn includes the Recent Chanos plus five fossil genera, grouped in two subfamilies: Chaninae (( Chanos +† Tharrhiai) + † Parachanos +† Dastilbe ) and † Rubiesichthyinae († Rubiesichthys +† Gordichthys ). † Aethalionopsis is the sister-group to the Chanidae. Gonorynchoidei includes two families Gonorynchidae and Kneriidae. Gonorynchidae is formed by ( Gonorynchus, † Notogoneus ) and four fossil taxa of uncertain definition and interrelationships: †Charitosomus, † Charitopsis, † Ramallichthys, and †fudeichthys. The last four genera were previously included in the families †Charitosomidae and †Judeichthyidae, which could not be supported as monophyletic in this analysis. Kneriidae consists of two subfamilies Phractolaeminae with one genus Phractolaemus, and Kneriinae which includes (( Kneria + Parakneria ) + ( Grasseichthys + Cromeria )), the latter two being paedomorphic forms. The Phractolaeminae and the Kneriinae are freshwater African taxa with no known fossil record. The order Gonorynchiformes is represented herein by 18 genera, extending back to the Early Cretaceous. More work is required to clarify the interrelationships of the Gonorynchidae and the paedomorphic characters that apparently played an important role in the evolution of this morphologically diverse group of fishes.  相似文献   

20.
A new mantispid genus and species Symphrasites eocenicus gen. sp. nov. is described from the Middle Eocene of the Messel Pit fossil site, Germany. It has been placed, with confidence, in the subfamily Symphrasinae, the fossils of which were previously unknown. A review of the known fossil species of Mantispidae is provided, and their systematic placements are discussed. Liassochrysa stigmatica Ansorge & Schlüter, 1990 is assigned to Mantispidae, and therefore Liassochrysidae is a new synonym of Mantispidae; a second, more complete specimen of Mesomantispa sibirica Makarkin, 1997 is described from the Early Cretaceous Baissa locality, Russia; Mantispidiptera Grimaldi, 2000 is excluded from the family; Vectispa Lambkin, 1986 is referred to subfamily Mantispinae; and the assignment of Whalfera Engel, 2004 to Rhachiberothidae is validated. The origin and palaeobiogeography of the mantispids are briefly discussed: the concept of ousted relicts – which assumes that former widely distributed taxa were replaced with groups originating in the tropics – is assumed to best explain the present distribution of the family.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 701–716.  相似文献   

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