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1.
Richard E. Triemer Eric Linton Woongghi Shin Alejandra Nudelman Anna Monfils Matthew Bennett Stacy Brosnan 《Journal of phycology》2006,42(3):731-740
A Bayesian analysis, utilizing a combined data set developed from the small subunit (SSU) and large subunit (LSU) rDNA gene sequences, was used to resolve relationships and clarify generic boundaries among 84 strains of plastid‐containing euglenophytes representing 11 genera. The analysis produced a tree with three major clades: a Phacus and Lepocinlis clade, a Discoplastis clade, and a Euglena, Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena clade. The majority of the species in the genus Euglena formed a well‐supported clade, but two species formed a separate clade near the base of the tree. A new genus, Discoplastis, was erected to accommodate these taxa, thus making the genus Euglena monophyletic. The analysis also supported the monophyly of Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena, which formed two subclades sister to the Euglena clade. Colacium, Trachelomonas, and Strombomonas, all of which produce copious amounts of mucilage to form loricas or mucilaginous stalks, formed a well‐supported lineage. Our analysis supported retaining Strombomonas and Trachelomonas as separate genera. Monomorphina and Cryptoglena formed two well‐supported clades that were sister to the Colacium, Trachelomonas, and Strombomonas clade. Phacus and Lepocinclis, both of which have numerous small discoid chloroplasts without pyrenoids and lack peristaltic euglenoid movement (metaboly), formed a well‐supported monophyletic lineage that was sister to the larger Euglena through Cryptoglena containing clade. This study demonstrated that increased taxon sampling, multiple genes, and combined data sets provided increased support for internal nodes on the euglenoid phylogenetic tree and resolved relationships among the major genera in the photosynthetic euglenoid lineage. 相似文献
2.
Molecular phylogeny,biogeography and chromosome evolution of Malagasy dwarf geckos of the genus Lygodactylus (Squamata,Gekkonidae)
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Marcello Mezzasalma Franco Andreone Gennaro Aprea Frank Glaw Gaetano Odierna Fabio M. Guarino 《Zoologica scripta》2017,46(1):42-54
We performed a phylogenetic analysis using nuclear (RAG‐1, RAG‐2) and mitochondrial (16S) markers, a statistical Bayesian reconstruction of ancestral distribution areas and a karyological analysis on most Malagasy species of the gekkonid genus Lygodactylus. The phylogenetic analysis largely confirms major basal branching pattern of previous molecular studies, but highlights significant differences concerning both the relationships between different species groups as well as those within groups. The biogeographic analysis supports a Malagasy origin of Lygodactylus, an oversea dispersal to continental Africa and a return to Madagascar. The L. madagascariensis group (also including a new candidate species identified herein) is the most basal clade in Lygodactylus, and the sister group of a clade with all the remaining species. The second most basal clade is the L. verticillatus group, placed as the sister group of a clade comprising African and Malagasy species. The sister lineage of the L. verticillatus group originated the African radiation through an oversea dispersal out of Madagascar. Eventually, the sister lineage of the L. capensis group originated secondary dispersals from Africa to Madagascar. In Madagascar, lineage diversification in different species groups mainly occurred from southern to northern and eastern regions. Dispersal, vicariance and paleoclimatic refugia probably played a relevant role in the evolutionary history of closely related taxa and in speciation mechanisms. The cytogenetic analysis evidenced a high karyotypic variability in Lygodactylus (from 2n = 34 to 2n = 40), which is at least partly consistent with the phylogenetic relationships and the composition of the various species group. Chromosome evolution occurred independently in different lineages, mainly through a reduction in the chromosome number and starting from a putative primitive karyotype of 2n = 40 with all telocentric elements. 相似文献
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Luis Cadahía Josef Harl Michael Duda Helmut Sattmann Luise Kruckenhauser Zoltn Fehr Laura Zopp Elisabeth Haring 《Journal of Zoological Systematics and Evolutionary Research》2014,52(2):163-169
The phylogenetic relationships among genera of the subfamily Ariantinae (Pulmonata, Helicidae), especially the sister‐group relationship of Cylindrus obtusus, were investigated with three mitochondrial (12S rRNA, 16S rRNA, Cytochrome c oxidase subunit I) and two nuclear marker genes (Histone H4 and H3). Within Ariantinae, C. obtusus stands out because of its aberrant cylindrical shell shape. Here, we present phylogenetic trees based on these five marker sequences and discuss the position of C. obtusus and phylogeographical scenarios in comparison with previously published results. Our results provide strong support for the sister‐group relationship between Cylindrus and Arianta confirming previous studies and imply that the split between the two genera is quite old. The tree reveals a phylogeographical pattern of Ariantinae with a well‐supported clade comprising the Balkan taxa which is the sister group to a clade with individuals from Alpine localities. Additional lineages representing samples from southern Alpine localities as well as from Slovakia split from more basal nodes, but their relationships are not clearly resolved. To achieve more definitive conclusions concerning the geographical origin of Ariantinae, still more sequence data are needed to obtain a tree with better resolution of basal nodes. The genetic data also provided new insights concerning the genus Cepaea, which was used as one of the outgroup taxa. Cepaea vindobonensis is only distantly related to Cepaea nemoralis and Cepaea hortensis, the latter two being more closely related to Eobania vermiculata. Thus, in our tree, the genus Cepaea is paraphyletic. 相似文献
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The microsporidium Heterovesicula cowani, discovered in 1985, was initially identified as Vairimorpha sp. because it produces two types of spores: Nosema-like diplokaryotic spores and Thelohania-like mononuclear meiospores. However, light and electron microscopy studies revealed characters that did not fit any known microsporidian genera, and a new monotypic genus Heterovesicula was erected. The goal of this study was to test the validity of the genus Heterovesicula by molecular characterization of H. cowani and to assess its phylogenetic relationships to other microsporidia from insects. DNA from spores stored at −32 °C since 1992 was isolated and PCR-amplified with V1-1492 primers to obtain a partial small subunit ribosomal RNA gene sequence of 1165 bp, which was submitted to GenBank (Accession No. EU275200). Neighbor joining, maximum parsimony and maximum likelihood analyses performed against 18 microsporidia sequences, placed H. cowani as a sister taxon to the Nosema–Vairimorpha clade. The consensus of these analyses suggests that the Heterovesicula–Nosema–Vairimorpha group forms a dichotomy with the Encephalitozoon spp. branch. Other microsporidia parasitizing Orthoptera fell into two unrelated (or distantly related) lineages of terrestrial microsporidia: the Liebermannia spp. branch forms a dichotomy with Orthosomella operophterae within the Endoreticulatus–Orthosomella–Liebermannia group; and the Paranosema spp. branch clusters together with the Tubulinosema–Systenostrema lineage. The minimum pairwise distance in Kimura-2-Parameter analysis among 18 analyzed sequences was 0.37, which supports well the generic status for Heterovesicula. The obtained phylogenetic trees suggest that H. cowani is related to the Vairimorpha necatrix group, but not to other insect microsporidia producing octospores. 相似文献
7.
The phylogeny of Anophelinae revisited: inferences about the origin and classification of Anopheles (Diptera: Culicidae)
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The evolution of anopheline mosquitoes (Culicidae: Anophelinae) has been the subject of speculation and study for decades, but a comprehensive phylogeny of these insects is far from complete. The results of phylogenetic studies based on morphological and molecular data sets are conspicuously ambiguous. Here, we revisit the phylogenetic relationships of anopheline mosquitoes using state‐of‐the‐art software and cladistic methods to analyse the data set of Harbach & Kitching (2005). We present a refined interpretation of relationships based on analyses of a revised data set that includes an additional species. Implied weighting analyses were conducted with TNT with the concavity constant K ranging from 1 to 33. We determined the optimal K value by summing the GC supports for each MPC and selected the tree with the highest support, K = 30, as the preferred cladogram. We then collapsed the branches with GC support < 1 to obtain the ‘best’ topography of relationships. Genus Chagasia is the basalmost taxon of Anophelinae, and genus Anopheles is recovered as monophyletic but only if Anopheles implexus is excluded and genus Bironella is subordinated within it. The Afrotropical An. implexus is recovered as the sister to all other anophelines, and Christya Theobald, stat. nov., is elevated from synonymy with Anopheles Meigen as a subgenus to accommodate it. The other anophelines comprise two large clades. The first includes the reciprocally monophyletic subgenera Kerteszia + Nyssorhynchus; the second consists of subgenus Cellia as the sister to a heterogeneous clade that includes genus Bironella and subgenera Anopheles, Baimaia, Lophopodomyia and Stethomyia of genus Anopheles. The sister relationship of Cellia and the heterogeneous clade is lost when the branches with GC <1 are collapsed. The monophyly and non‐monophyly of the informal subordinate taxa of subgenera Nyssorhynchus, Cellia and Anopheles, and also evolutionary scenarios, are discussed in relation to previous studies. 相似文献
8.
We report a new heterotrophic cryptomonad Hemiarma marina n. g., n. sp. that was collected from a seaweed sample from the Republic of Palau. In our molecular phylogenetic analyses using the small subunit ribosomal RNA gene, H. marina formed a clade with two marine environmental sequences, and the clade was placed as a sister lineage of the freshwater cryptomonad environmental clade CRY1. Alternatively, in the concatenated large and small subunit ribosomal RNA gene phylogeny, H. marina was placed as a sister lineage of Goniomonas. Light and electron microscopic observations showed that H. marina shares several ultrastructural features with cryptomonads, such as flattened mitochondrial cristae, a periplast cell covering, and ejectisomes that consist of two coiled ribbon structures. On the other hand, H. marina exhibited unique behaviors, such as attaching to substrates with its posterior flagellum and displaying a jumping motion. H. marina also had unique periplast arrangement and flagellar transitional region. On the basis of both molecular and morphological information, we concluded that H. marina should be treated as new genus and species of cryptomonads. 相似文献
9.
Balaenidae (right whales) are large, critically endangered baleen whales represented by four living species. The evolutionary relationships of balaenids are poorly known, with the number of genera, relationships to fossil taxa, and position within Mysticeti in contention. This study employs a comprehensive set of morphological characters to address aspects of balaenid phylogeny. A sister‐group relationship between neobalaenids and balaenids is strongly supported, although this conflicts with molecular evidence, which may be an artifact of long‐branch attraction (LBA). Monophyly of Balaenidae is supported, and three major clades are recognized: (1) extinct genus Balaenula, (2) extant and extinct species of the genus Eubalaena, and (3) extant and extinct species of the genus Balaena plus the extinct taxon, Balaenella. The relationships of these clades to one another, as well as to the early Miocene stem balaenid, Morenocetus parvus, remain unresolved. Pliocene taxa, Balaenula astensis and Balaenula balaenopsis, form a clade that is the sister group to the Japanese Pliocene Balaenula sp. Eubalaena glacialis and Pliocene Eubalaena belgica, are in an unresolved polytomy with a clade including E. japonica and E. australis. Extant and fossil species of Balaena form a monophyletic group that is sister group to the Dutch Pliocene Balaenella, although phylogenetic relationships within Balaena remain unresolved. 相似文献
10.
E. E. Schilling 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(6-7):925-933
Chloroplast DNA (cpDNA) restriction site data were used to analyze phylogenetic relationships within Helianthus. Data from new samples were consistent with previous results and showed the genus to be a well-defined (11 site changes)
lineage within subtribe Helianthinae. The affinities of 2 species, Viguiera similis and V. phenax (V. ludens) that have sometimes been included in Helianthus were shown to lie outside the genus. The two species of Phoebanthus, however, formed a phylogenetic ingroup to the perennial Helianthus. Within the genus, cpDNA data indicated that there are four distinct phylogenetic lineages. Two of the lineages each contained
a single, annual species (H. agrestis and H. porteri, respectively). The remaining annual species collectively formed a third lineage (sect. Helianthus). The fourth lineage contained all of the perennial species, including those of Phoebanthus. Within the perennial lineage, there was little variation in restriction site characters. The 3 species of series Pumili formed a paraphyletic group at the base of the perennial lineage, and the 3 species of series Ciliares formed a group that was supported by a single restriction site character.
Received: 2 September 1996 / Accepted: 25 October 1996 相似文献
11.
Robert C. Jadin Ronald L. Gutberlet Jr Eric N. Smith 《Journal of Zoological Systematics and Evolutionary Research》2010,48(4):360-365
The jumping pitvipers, genus Atropoides, occur at low to middle elevations throughout Middle America. Recent molecular phylogenetic analyses have included all six species of Atropoides, but only two studies have found Atropoides to be monophyletic and questions persist about relationships within the A. nummifer complex. In this study, our phylogenetic analyses of morphological data provide strong support for the monophyly of Atropoides and recover relationships within the genus that are mostly congruent with those of recent molecular studies, further supporting the evolutionary and biogeographic hypotheses proposed in those studies. Our analyses find support for a sister relationship between A. picadoi and the other Atropoides species and an A. occiduus–A. indomitus clade sister to an A. nummifer–A. mexicanus–A. olmec clade. Within the A. nummifer complex, we find A. mexicanus and A. olmec to be sister species to the exclusion of A. nummifer. We include morphological synapomorphies to support each clade within Atropoides and describe and illustrate the hemipenes of each species. In addition, we discuss the importance of morphological phylogenetics and the functionality and limitations of hemipenial data in systematics. 相似文献
12.
Anja Engleder Elisabeth Haring Sebastian Kirchhof Werner Mayer 《Journal of Zoological Systematics and Evolutionary Research》2013,51(2):132-143
Eremiadinae, one of three subfamilies of Lacertidae, are distributed throughout Asia and Africa. Previous phylogenetic studies suggested that one of the main groups of Eremiadinae (the Ethiopian clade) consist of two clades with predominately East‐African and South‐African distribution. Yet, especially the latter one, which includes the genera Pedioplanis, Meroles, Ichnotropis, Tropidosaura and Australolacerta, was not well supported in the molecular phylogenetic analysis. In this study, we analysed the phylogenetic relationships among the genera of the ‘South African clade’ to assess whether this group actually forms a highly supported clade and to address questions concerning the monophyly of the genera. We sequenced sections of the widely used mitochondrial genes coding for 16S rRNA, 12S rRNA and cytochrome b (altogether 2045 bp) as well as the nuclear genes c‐mos, RAG‐1, PRLR, KIF24, EXPH5 and RAG‐2 (altogether 4473 bp). The combined data set increased the support values for several nodes considerably. Yet, the relationships among five major lineages within the ‘South African clade’ are not clearly resolved even with this large data set. We interpret this as a ‘hard polytomy’ due to fast radiation within the South African lacertids. The combined tree based on nine marker genes provides strong support for the ‘South African Clade’ and its sister group relationship with the ‘East African Clade’. Our results confirm the genus Tropidosaura as a monophylum, while Ichnotropis is paraphyletic in our trees: Ichnotropis squamulosa appears more closely related to Meroles than to Ichnotropis capensis. Furthermore, the monophyly of Meroles is questionable as well. Based on our results, I. squamulosa should be transferred from Ichnotropis into the genus Meroles. Also, the two species of Australolacerta (A. australis and A. rupicola) are very distantly related and the genus is perhaps paraphyletic, too. Finally we propose a phylogeographical scenario in the context of palaeoclimatic data and compare it with a previously postulated hypothesis. 相似文献
13.
Michael Gruenstaeudl Estrella Urtubey Robert K. Jansen Rosabelle Samuel Michael H.J. Barfuss Tod F. Stuessy 《Molecular phylogenetics and evolution》2009,51(3):572-587
Subfamily Barnadesioideae (Asteraceae) consists of nine genera and 91 species endemic to South America. They include annual and perennial herbs, arching shrubs and trees up to 30 m tall. Presumed sister to all other Asteraceae, its intergeneric relationships are key to understanding the early evolution of the family. Results of the only molecular study on the subfamily conflict with relationships inferred from morphology. We investigate inter- and intrageneric relationships in Barnadesioideae with novel DNA sequence data and morphological characters using parsimony, likelihood and Bayesian inference. All results verify Barnadesioideae as monophyletic and sister to the rest of the family. A basal split within the subfamily is recognized, with Chuquiraga, Doniophyton and Duseniella in one clade, and Arnaldoa, Barnadesia, Dasyphyllum, Fulcaldea, Huarpea and possibly Schlechtendalia in another. The largest genus, Dasyphyllum, is revealed as biphyletic with the two clades separating along subgeneric and geographic lines. Schlechtendalia, suggested as the earliest diverging lineage of the subfamily by morphological studies and parsimony analyses, is found in a more derived position under model-based inference methods. Competing phylogenetic hypotheses, both previous and present, are evaluated using likelihood-based tests. Evolutionary trends within Barnadesioideae are inferred: hummingbird pollination has developed convergently at least three times. An early vicariance in the subfamily’s distribution is revealed. X = 9 is supported as the ancestral base chromosome number for both Barnadesioideae and the family as a whole. 相似文献
14.
A clade where the most halotolerant fungus in the world – Hortaea werneckii, belongs (hereafter referred to as Hortaea werneckii lineage) includes five species: Hortaea werneckii, H. thailandica, Stenella araguata, Eupenidiella venezuelensis, and Magnuscella marina, of which the first species attracts increasing attention of mycologists. The species diversity and phylogenetic relationships within this lineage are weakly known. In this study two moderately halophilic black yeast strains were isolated from brine of graduation tower in Poland. Molecular phylogenetic analyses based on the rDNA ITS1-5.8S-ITS2 (=ITS), rDNA 28S D1–D2 (=LSU), and RNA polymerase II (rpb2) sequences showed that the two strains belong to Hortaea werneckii lineage but cannot be assigned to any described taxa. Accordingly, a new genus and species, Salinomyces and Salinomyces polonicus, are described for this fungus. Furthermore, molecular phylogenetic analyses have revealed that Hortaea thailandica is more closely related to S. polonicus than to H. werneckii. A new combination Salinomyces thailandicus is proposed for this fungus. 相似文献
15.
Marcel G. Hermes Gabriel A. R. Melo James M. Carpenter 《Cladistics : the international journal of the Willi Hennig Society》2014,30(5):453-484
Cladistic analyses were carried out to infer the phylogenetic relationships among taxa that were originally part of the large genus Eumenes. Terminals belonging to other eumenine lineages were also included, as well as terminals from other vespid subfamilies. Analyses under equal weights and implied weights were carried out, and better results were obtained with the latter. The results corroborated the monophyly of Eumeninae, and recovered Zethini sensu lato as the sister‐lineage to the remaining eumenines. Eumenes sensu lato as originally recognized is paraphyletic relative to Odynerus sensu lato. A natural classification at the tribal level congruent with the phylogenetic results may be proposed, and the names Zethini, Odynerini, and Eumenini are already available. This is the most comprehensive phylogeny of the Eumeninae to date. A new generic synonymy is Alfieria Giordani Soika, 1934 = Delta de Saussure, 1855. 相似文献
16.
Polotow, D. & Brescovit, A. D. (2010). Phylogenetic relationships of the Neotropical spider genus Itatiaya (Araneae). —Zoologica Scripta, 40, 187–193. A cladistic analysis using parsimony under equal weights is applied to test the phylogenetic relationships of Itatiaya Mello‐Leitão, previously described in Ctenidae. The data matrix comprised 25 taxa scored for a total of 47 characters. The cladistic analysis yielded two equally parsimonious trees of 124 steps. The consensus of the two most parsimonious trees is used to discuss the phylogenetic relationships and justify taxonomic modifications. The results indicate that this genus is a representative of Zoropsidae, which is newly recorded from the Neotropical region. The monophyly of Itatiaya is supported by three non‐ambiguous synapomorphies and three homoplastic synapomorphies. A new diagnosis is provided for Itatiaya. Itatiaya pucupucu is placed as sister species to the remaining species of the genus. A polytomic clade composed of Itatiaya modesta, Itatiaya iuba, Itatiaya apipema and the clade formed by Itatiaya tacamby + Itatiaya pykyyra is supported by the presence of modified cylindrical gland spigots. Additionally, the male of I. pykyyra Polotow & Brescovit is described for the first time. 相似文献
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Yong-Ming Yuan Sbastien Wohlhauser Michael Mller Philippe Chassot Guilhem Mansion Jason Grant Philippe Küpfer Jens Klackenberg 《Molecular phylogenetics and evolution》2003,28(3):500
Both chloroplast trnL (UAA) intron and nuclear ribosomal ITS sequences highly confirmed the monophyly of the tribes of the Gentianaceae defined by the recent classification, and revealed the tribe Exaceae as a basal clade just next to the basal-most lineage, the tribe Saccifolieae. Within the tribe Exaceae, Sebaea (except Sebaea madagascariensis) appeared as the most basal clade as the sister group to the rest of the tribe. The Madagascan endemic genera Gentianothamnus and Tachiadenus were very closely related to each other, together standing as sister to a clade comprising Sebaea madagascariensis, Ornichia, and Exacum. The saprophytic genus Cotylanthera nested deeply inside Exacum. Sebaea madagascariensis was shown closer to the Madagascan endemic genus Ornichia than to any other sampled Sebaea species. Exacum appeared as the most derived taxon within this tribe. The topology of the phylogenetic trees conform with the Gondwana vicariance hypothesis regarding the biogeography of Exaceae. However, no evidence for matching the older relationships within the family to the tectonic history could be corroborated with various divergence time analyses. Divergence dating estimated a post-Gondwana diverging of the Gentianaceae about 50 million years ago (MYA), and the tribe Exaceae as about 40 MYA. The Mozambique Channel land-bridge could have played an important role in the biogeographic history of the tribe Exaceae. 相似文献
19.
Comprehensive phylogeny of the laughingthrushes and allies (Aves,Leiothrichidae) and a proposal for a revised taxonomy
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Alice Cibois Magnus Gelang Per Alström Eric Pasquet Jon Fjeldså Per G. P. Ericson Urban Olsson 《Zoologica scripta》2018,47(4):428-440
DNA phylogenies have gradually shed light on the phylogenetic relationships of the large babbler group. We focus in this study on the family Leiothrichidae (laughingthrushes and “song babblers”), which represents the largest clade of babblers in terms of species diversity. Our phylogeny includes all genera and 82% of the recognized species, using mitochondrial and nuclear loci. The sister group to Leiothrichidae is composed of the Pellorneidae (“jungle babblers”) plus the genus Alcippe. Within Leiothrichidae, four strongly supported primary clades (A–D) are recovered. Clade A includes Grammatoptila, Laniellus and Cutia. Clade B includes a large group of laughingthrushes, all of them classified in Trochalopteron. In Clade C, the two laughingthrushes endemic to southern India, T. fairbanki and T. cachinnans, which have recently been proposed to be placed in the newly erected genus Montecincla, form a sister clade to the group comprising the “song babblers” (Lioptila, Leiothrix, Heterophasia, Minla, Liocichla, Actinodura, Chrysominla, Siva, and Sibia). Clade D includes the African babblers (Turdoides, Phyllanthus, Kupeornis), Asian relatives (Argya, Acanthoptila, Chatarrhaea) and all remaining laughingthrushes (Garrulax). The time estimates suggest that the early diversification of the Leiothrichidae occurred in the mid‐Miocene, a period that corresponds to the diversification of many passerine groups in Asia. A revised taxonomic classification of the family is proposed in the light of these results. 相似文献
20.
Systematics and phylogeny of Vasseuromys (Mammalia,Rodentia, Gliridae) with a description of a new species from the late Miocene of eastern Europe
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Vasseuromys is a species‐rich genus of small‐ to medium‐sized glirids spanning the latest Oligocene to late Miocene of Europe and western Asia. Despite extensive discoveries over the past 50 years, little phylogenetic work has been done on Vasseuromys. This study presents the first phylogenetic analysis of the genus that includes all the described species and a new taxon Vasseuromys tectus sp. nov. from the late Miocene of eastern Europe, providing the first insights into the evolutionary relationships within the clade. Results suggest that the genus is clearly paraphyletic. Two strongly supported genus‐level clades are recognized within ‘Vasseuromys’: a restricted Vasseuromys clade (containing the three species, V. pannonicus, V. rugosus and V. tectus) and the Glirulus clade that includes ‘Vasseuromys’ duplex. The remaining ‘Vasseuromys’ species are found to constitute a set of paraphyletic taxa, with the polyphyletic ‘Ramys’ nested within it. The genus Gliruloides is synonymized with Glirulus. Vasseuromys tectus sp. nov. is the most derived member of the genus in having a greater number of cheek teeth ridges including constantly present anterotrope, centrotrope, second prototrope on M1–2, third metatrope on M2, two to three posterotropids on p4 and strong ectolophids on lower molars. The results of the study confirm a European origin for Vasseuromys while suggesting that the late Miocene species of the genus dispersed from the east in the early Turolian. 相似文献