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1.
Abstract: The family Acrochordiceratidae Arthaber, 1911 ranges in age from latest Spathian to the middle/late Anisian boundary, and it represents a major component of ammonoid faunas during that time. The middle Anisian genus Acrochordiceras Hyatt, 1877 is the most widespread taxon of the family and occurs abundantly worldwide within the low paleolatitude belt. However, there is a profusion of species names available for Acrochordiceras. This excessive diversity at the species level essentially results from the fact that sufficiently large samples were not available, thus leading to a typological approach to its taxonomy. Based on new extensive collections obtained from the Anisian (Middle Triassic) Fossil Hill Member (Star Peak Group, north‐west Nevada) for which a high resolution biostratigraphic frame is available, the taxonomy and biostratigraphy of the genus Acrochordiceras Hyatt, 1877 is herein revised with respect to its intra‐specific variation. Morphological and biometric studies (c. 550 bedrock‐controlled specimens were measured) show that only one species occurs in each stratigraphic level. Continuous ranges of intra‐specific variation of studied specimens enable us to synonymize Haydenites Diener, 1907, Silesiacrochordiceras Diener, 1916 and Epacrochordiceras Spath, 1934 with Acrochordiceras Hyatt, 1877. Three stratigraphically successive species are herein recognized in the low paleolatitude middle Anisian faunas from Nevada: A. hatschekii (Diener, 1907), A. hyatti Meek, 1877 and A. carolinae Mojsisovics, 1882. Moreover, an assessment of intra‐specific variation of the adult size range does not support recognition of a dimorphic pair (Acrochordiceras and Epacrochordiceras) as previously suggested by other workers (Epacrochordiceras is the compressed and weakly ornamented end‐member variant of Acrochordiceras). The successive middle Anisian species of Acrochordiceras form an anagenetic lineage characterized by increasing involution, adult size and intra‐specific variation. This taxonomic revision based on new bedrock‐controlled collections is thus an important prerequisite before studying the evolution of the group.  相似文献   

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The phylogeny of ligulate and sulfuric‐acid containing species of Desmarestia, occurring worldwide from polar to temperate regions, was revised using a multigenic and polyphasic approach. Sequence data, gametophyte characteristics, and sporophyte morphology support reducing a total of 16 taxa to four different species. (1) D. herbacea, containing broad‐bladed and highly branched forms, has dioecious gametophytes. The three other species have monoecious gametophytes: (2) D. ligulata which is profusely branched and, except for one subspecies, narrow‐bladed, (3) Japanese ligulate Desmarestia, here described as D. japonica sp. nov., which is morphologically similar to D. ligulata but genetically distant from all other ligulate taxa. This species may have conserved the morphology of original ligulate Desmarestia. (4) D. dudresnayi, including unbranched or little branched broad‐bladed taxa. A figure of the holotype of D. dudresnayi, which was lost for decades, was relocated. The taxonomy is complemented by a comparison of internal transcribed spacer and cytochrome c oxidase subunit I (cox1) as potential barcode loci, with cox1 offering good resolution, reflecting species delimitations within the genus Desmarestia.  相似文献   

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Abstract A new species of the genus Linshcosteus Distant, 1904 (Hemiptera: Reduviidae: Triatominae) is described from specimens collected near Kalakkadu, Tamil Nadu state, southern India. Specimens were found in deep crevices between rocks, in a region of semi‐arid scrub jungle. The distinctiveness of the new species was demonstrated by a morphometric analysis including the five previously described species of Linshcosteus, all from India. Nine measurements of the head were used in an isometric size‐free principal component analysis. In terms of discrete morphology the new species, Linshcosteus karupus sp.n. Galvão, Patterson, Rocha & Jurberg differs from the most similar one, L. kali Lent & Wygodzinsky, 1979 , by its very prominent anterolateral projections of the pronotum, by the length to width ratio of the pronotum, by the pilosity of the head and several other characters, including phallic structures. A revised key is presented for the six species of the genus.  相似文献   

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The taxonomy of common northern nudibranch molluscs of the genus Dendronotus in the vast cold regions of Eurasia remains largely unknown. Abundant material collected in many localities from the Barents Sea, via the Arctic region, to the north‐west Pacific was analysed for the first time. An integrated approach combining morphological and ontogenetic data with molecular four‐gene (COI, 16S, H3, and 28S) analysis reveals seven species, including three previously undescribed. Dendronotus frondosus (Ascanius, 1774) and Dendronotus dalli Bergh, 1879 were commonly considered as amphiboreal species; however, according to this study they are restricted to the North Atlantic and the North Pacific, respectively. In the north‐west Pacific two new species were discovered, D endronotus kamchaticus sp. nov. and D endronotus kalikal sp. nov. , that are externally similar to D. frondosus, but that show significant distance according to molecular analysis and are considerably different in radular morphology. In the North Atlantic a new species D endronotus niveus sp. nov. , sibling to North Pacific D. dalli, is revealed. The separate status of North Atlantic Dendronotus lacteus (Thompson, 1840) is confirmed, including considerable range extension. The essential similarity of early ontogenetic stages of radular development common for species with disparate adult radular morphology (such as D. frondosus and D. dalli) is shown, and its importance for taxonomy is discussed. © 2015 The Linnean Society of London  相似文献   

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Kotov and Štifter (2006) revised the taxonomy of the genus Ilyocryptus Sars, 1862 (Branchiopoda: Anomopoda: Ilyocryptidae) and concluded that 28 species can be recognized as valid for the world fauna. In order to test phylogenetic relationships between the species and to contribute to a better understanding of the genus, a cladistic (using branch‐and‐bound search) analysis was conducted for 25 Ilyocryptus species (two of them with two subspecies). In total, 32 morphological characters were used. An evolutionary‐morphological interpretation of the results was also made. Phylogenetic analysis revealed that Ilyocryptus elegans is an earlier derived member of the genus, while other species are separated into two main branches: agilis ‐ and sordidus ‐lines (without reference to type of moulting). Species with incomplete moulting and species with complete moulting do not form separate clusters, suggesting an independent origin of incomplete moulting within different species groups. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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We investigated the phylogeny, taxonomy and biogeography of the Eritreo-Arabian genus Echidnopsis Hook. f. (Apocynaceae-Asclepiadoideae). Phylogenetic reconstructions based on nrITS sequence data were obtained using maximum likelihood and parsimony analyses. The results reveal two weakly supported clades, each with a mix of African and Arabian taxa, including the genus Rhytidocaulon, and with four Socotran species forming a subclade of their own. Rather than a vicariance origin of these island elements, our data suggest a single dispersal event from eastern Africa. Echidnopsis thus parallels biogeographic patterns found for other Socotran endemic plants. Our revised taxonomy recognizes 28 species and 4 subspecies in the genus. Two new combinations, E. planiflora subsp. chrysantha and E. sharpei subsp. bavazzani are proposed.  相似文献   

12.
Although Tropicoperdix has been considered to be either a full genus or a species complex within the Phasianid genus Arborophila (hill partridges), there is long‐standing uncertainty regarding the degree of difference that warrants generic separation, including reported anatomical cranial differences. In addition, the intra‐generic taxonomy remains under dispute. Most studies hypothesize that Tropicoperdix comprises three species, while others postulate from one to four species. However, no molecular study has been performed to clarify the systematic and taxonomic uncertainties surrounding Tropicoperdix. In the present study, we performed a series of molecular phylogenetic analyses of Tropicoperdix and Arborophila taxa based on two mitochondrial genes and five nuclear introns. All the results are consistent with the finding that Tropicoperdix and Arborophila are phylogenetically distinct and distant genera, although the precise phylogenetic position of Tropicoperdix remains undetermined. Retrospective examination of external characteristics also supports the generic separation, as well as providing evidence of remarkable multiple character convergence. We propose that Tropicoperdix comprises at least two full species based on mitochondrial data obtained from museum specimens by using a next‐generation sequencing method. © 2015 The Linnean Society of London  相似文献   

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The investigation into the cockroach genus Paranauphoeta Brunner von Wattenwyl is insufficient, and there is a lack of taxonomic documentation of this genus from China. Recently, the authors obtained some newly collected specimens which facilitated this study. In this paper the generalized morphology of Paranauphoeta is interpreted in detail, particularly for the male phallic complex, which is illustrated as a whole rather than in pieces. The taxonomy of Paranauphoeta species from China is revised. One out of four species recorded from China, P. indica Saussure & Zehntner, is removed; instead, P. kirby nom. nov. is recorded from China. Together with three new species described in this paper, namely, P. anulata sp. nov. , P. brachyptera sp. nov. and P. lineola sp. nov. , a total of seven Paranauphoeta species are now known to occur in China, whose habitus photos are provided. The new species confirm that this genus is wing‐polymorphic. Male structures, if available, are illustrated. Female structures and oothecae, of which knowledge is limited in this genus and also in cockroach taxonomy, are illustrated or documented, respectively. A key to and a distribution map of the Paranauphoeta species from China are provided. In addition, P. atra Shelford nom. rev. , P. sinica Bey‐Bienko stat. nov. and P. vietnamensis Anisyutkin stat. nov. are regarded as valid separate species.  相似文献   

15.
A new Category 1 species of Acanthobothrium van Beneden, 1850 is described from the cowtail stingray Pastinachus atrus (Macleay) collected from the Gulf of Carpentaria near Weipa, Queensland, Australia. This species is unique among Acanthobothrium Category 1 species in that it retains gravid proglottids on its strobila. It differs further from the 34 other Category 1 species in total length, proglottid number and testis number. The host identities of other Acanthobothrium species reported from Pastinachus are revised based on recent taxonomic work on rays of this genus. Given the revised host taxonomy, according to which P. atrus is the only member of its genus occurring off Australia, this should be considered to be the fifth species of Acanthobothrium reported from this Australian endemic species.  相似文献   

16.
The fish belonging to Gerreidae are common representatives of the coastal ichthyofauna of the tropics and subtropics of the world. The genus Diapterus has a neotropical distribution and currently includes four species: two in the Atlantic Ocean [Irish mojarra D. auratus Ranzani 1842 and rhombic mojarra D. rhombeus (Cuvier 1829)] and two in the Pacific Ocean [short‐beaked mojarra D. brevirostris (Sauvage 1879) and golden mojarra D. aureolus (Jordan & Gilbert 1882)]. This genus has uncertain taxonomy based on the remarkable and dissimilar morphology of D. aureolus. We evaluated the taxonomy and phylogeny of Diapterus with statistical (canonical discriminant analysis) and phylogenetic analyses (maximum parsimony, maximum likelihood and Bayesian inference) of geometric morphometric data (relative warps) and molecular data (12Sr RNA, 16Sr RNA, COI and RAG1 sequences). Our results indicate that the genus Diapterus as we currently conceive it is a polyphyletic group: [(Gerres cinereusEucinostomus spp. (D. aureolus – (Eugerres spp. (D. auratus – (D. brevirostris – D. rhombeus)))))]. Therefore, a taxonomic rearrangement is needed. To preserve the monophyly of the group, our proposal is to remove D. aureolus and place it in a new monotypic genus. A neotype is designated for D. aureolus as well as an artificial identification key for the genera and the species treated in this article.  相似文献   

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Three new species of Lonchaeidae are described from material reared from fig syconia in Japan: Silba inubiwa sp. nov., S. ishigaki sp. nov. and S. japonica sp. nov. Based on the taxonomy of these and similar species the boundaries of the genus Silba are re‐evaluated, and, as a result, it is considered that Setisquamalonchaea Morge is synonymous with Silba Macquart. A revised key and generic notes on the tribe Lonchaeini are provided.  相似文献   

18.
All global genera of the fly family Conopidae are revised here. A cladistic analysis of 117 morphological characters recorded from 154 species, including representatives of 59 genera and subgenera, recovers a phylogenetic hypothesis for the family. This hypothesis is used as the basis of a new classification for the family. Both Sicini and Zodionini are removed from Myopinae and elevated to subfamilial status. A new tribe, Thecophorini, is proposed within Myopinae to accommodate Thecophora, Scatoccemyia, and Pseudoconops. Two genera, Pseudomyopa and Parazodion, are removed from Dalmanniinae and placed in Myopinae and Zodioninae, respectively. Conopinae is divided into 11 tribes, seven of which are newly described (Asiconopini, Caenoconopini, Gyroconopini, Microconopini, Neoconopini, and Siniconopini). Some examined species are transferred to different or new genera and subgenera. A new genus, Schedophysoconops gen. nov. , and subgenus Asiconops (Aegloconops) subgen. nov. within Conopinae are described. A review of character evolution and phylogeography is included in light of the new classification. A catalogue of all genus‐group names is included with new emendations noted.  相似文献   

19.
The mycalesine butterfly genus Heteropsis Westwood, 1850 (Satyrinae: Mycalesina) has recently been conceived to be represented in three major palaeotropical regions (Madagascar, Africa and Asia), but there has been no formal taxonomic treatment covering this entire group. Studies aimed at understanding the evolutionary success of Mycalesina in the Old World tropics have been hampered by the lack of both a robust phylogeny and a stable nomenclature for this satyrine subtribe. Here, we present a well‐supported molecular phylogeny based on 10 genes and 133 exemplar taxa, representing almost all known species groups of Heteropsis (s.l.), and including all but four known species in Madagascar. We also combine sequences of the exemplars with a morphological matrix of 428 characters. The widespread ‘Heteropsis clade’ is confirmed as monophyletic, but lineages in different geographic regions also form endemic and well‐supported clades with deep divergences among them. Here we establish this group as comprising three genera, Heteropsis (Malagasy region only), Telinga Moore, 1880 (Asia), and Brakefieldia gen.n. (Africa). We recover the genera Telinga and Brakefieldia as sisters with high support. Each genus is taxonomically characterized and a revised synonymic checklist is appended with new combinations and some changes in rank. With a well‐resolved topology and updates to the taxonomy of the group, researchers are now in a position to explore the drivers of the spectacular radiation of the group, notably in Madagascar, where the highest phenotypic and species diversity occurs. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:AAF9F440‐A2D6‐4483‐BF35‐9BC074D9D29B .  相似文献   

20.
We report the discovery of a new genus of heterolobosean flagellates, Dactylomonas gen. nov., with two species, D. venusta sp. nov. and D. crassa sp. nov. Phylogenetic analysis of the SSU rRNA gene showed that Dactylomonas is closely related to the amoeba Selenaion, the deepest‐branching lineage of Tetramitia. Dactylomonads possess two flagella, and ultrastructural studies revealed an unexpected organization of the flagellar apparatus, which resembled Pharyngomonada (the second lineage of Heterolobosea) instead of Tetramitia: basal bodies were orthogonal to each other and a putative root R1 was present in the mastigont. On the other hand, Dactylomonas displayed several features uncommon in Heterolobosea: a microtubular corset, a distinctive rostrum supported by the main part of the right microtubular root, a finger‐like projection on the proximal part of the recurrent flagellum, and absence of a ventral groove. In addition, Dactylomonas is anaerobic and seems to have lost mitochondrial cristae. Dactylomonas and Selenaion are accommodated in the family Selenaionidae fam. nov. and order Selenionida ord. nov. The taxonomy of Tetramitia is partially revised, and the family Neovahlkampfiidae fam. nov. is established.  相似文献   

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