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1.
Landouria omphalostoma n. sp. is described from northern Yunnan, China. The new species is placed in the genus Landouria Godwin-Austen, 1918 based on the presence of tuberculated flagellum and swollen basal part in the bursa copulatrix, and on the absence of dart sacs and mucous glands. L. omphalostoma n. sp. is characterized by a horizontal aperture of the shell which is unique in the genus. This feature resembles those of only two other camaenid/bradybaenid taxa, species of the Chinese genus Pseudaspasita Möllendorff, 1902 and species of the Japanese genus Coelorus Pilsbry, 1900. This is the first verified record of the genus in China and the easternmost record of Landouria. This paper provides the taxonomic ground work for further studies of the repeated evolution of a horizontal aperture.  相似文献   

2.
The limacoid land snail Asperitas Gude, 1911 encompasses several vividly coloured, yet poorly known species that are distributed throughout the Lesser Sunda Islands, Sulawesi, and the Moluccas. We examined the variation in shell morphology, including the use of geometric morphometrics, and reproductive anatomy of snails from Timor and several adjacent islands. These studies revealed that none of the taxa described from Timor and considered to be endemic to this island could be reliably distinguished from any of the others. In addition to the systematic ambiguity of morphological characteristics, we uncovered rather low amounts of genetic differentiation in the mitochondrial marker cytochrome c oxidase subunit I that was not consistent with the current taxonomy. Based on these observations, we conclude that there is just a single Asperitas species on Timor that exhibits notable variability in shell characters and body colour. This variability is ascribed to the combined effects of polymorphic colour patterns with locally varying selection in different habitats and along altitudinal gradients. Individuals from the adjacent islands of Flores, Sumbawa, Solor and Romang, which are deemed to represent distinct species-level taxa, exhibit similar amounts of variation in shell and body colour. They exhibit a consistent reproductive anatomy and overall negligible amounts of mitochondrial differentiation from the populations on Timor. Patterns in shell variation do not lend support to previously held ideas that different Sunda Islands harbour distinct radiations of polytypic Asperitas species. By contrast, we suggest that the taxonomic diversity of Asperitas has been overestimated for the over-reliance on shell features and that many presently accepted taxa are likely mere synonyms of fewer and more widespread species.  相似文献   

3.
ABSTRACT

The species of Satsuma are mostly endemic to East Asia except for one species distributed in Batan Island of the Philippines. More than 99% of the known species of this genus are endemic to the island environment. Only three species are currently known to occur on the mainland. Here we describe a new sinistral Satsuma species from China, Satsuma guandi n. sp. We studied the shell morphology and genital anatomy of the new species and reconstructed the molecular phylogeny of the genus based on partial nucleotide sequences of the mitochondrial gene cytochrome c oxidase subunit I and nuclear markers from the ribosomal RNA cistrons (the internal transcribed spacer and the external transcribed spacer regions). The new species differs from other sinistral Satsuma species by having a strongly angulated shell and an open dark brownish-red umbilicus. The new species also differed from all other sinistral congeners in details of its reproductive anatomy. The molecular analysis supports the validity of the new species within the genus Satsuma.  相似文献   

4.
In this study we compared the phylogeographic patterns of two Rusa species, Rusa unicolor and Rusa timorensis, in order to understand what drove and maintained differentiation between these two geographically and genetically close species and investigated the route of introduction of individuals to the islands outside of the Sunda Shelf. We analyzed full mitogenomes from 56 archival samples from the distribution areas of the two species and 18 microsatellite loci in a subset of 16 individuals to generate the phylogeographic patterns of both species. Bayesian inference with fossil calibration was used to estimate the age of each species and major divergence events. Our results indicated that the split between the two species took place during the Pleistocene, ~1.8 Mya, possibly driven by adaptations of R. timorensis to the drier climate found on Java compared to the other islands of Sundaland. Although both markers identified two well‐differentiated clades, there was a largely discrepant pattern between mitochondrial and nuclear markers. While nDNA separated the individuals into the two species, largely in agreement with their museum label, mtDNA revealed that all R. timorensis sampled to the east of the Sunda shelf carried haplotypes from R. unicolor and one Rusa unicolor from South Sumatra carried a R. timorensis haplotype. Our results show that hybridization occurred between these two sister species in Sundaland during the Late Pleistocene and resulted in human‐mediated introduction of hybrid descendants in all islands outside Sundaland.  相似文献   

5.
Aegista subchinensis (Möllendorff, 1884) is a widely distributed land snail species with morphological variation and endemic to Taiwan. Three genetic markers (partial sequence of the mitochondrial cytochrome c oxidase subunit I [COI], the 16S rDNA and the nuclear internal transcribed spacer 2 [ITS2]) were analysed to infer phylogenetic relationships and genetic divergence of closely related species of the genus Aegista, Aegista vermis (Reeve, 1852) and Aegista oculus (Pfeiffer, 1850). A new species from Aegista subchinensis has been recognized on the basis of phylogenetic and morphological evidences. The nominal new species, Aegista diversifamilia sp. n. is distinguished from Aegista subchinensis (Möllendorff, 1884) by its larger shell size, aperture and apex angle; wider umbilicus and flatter shell shape. The northernmost distribution of Aegista diversifamilia sp. n. is limited by the Lanyang River, which is presumed to mark the geographic barrier between Aegista diversifamilia sp. n. and Aegista subchinensis.  相似文献   

6.
Sophina is a poorly known and neglected genus due to the inaccessibility of the Salween Basin, Southern Myanmar. Taxonomic status, distribution, and phylogeny are being revised based on an integrative analysis of genitalia, radula, and molecular data. Morphological variation in shells and genitalia, together with a phylogenetic tree from concatenated data of mitochondrial and nuclear genes, revealed the existence of ten species/subspecies. Penial morphology and genetic divergence were generally consistent and useful in delimiting species, while shell characters showed little overall taxonomic utility in some species. Taxonomic placement of the previous subspecies “bensoni” shows clear distinction in both genitalia and molecular evidence, and is currently recognized as a distinct species. The nominal species “S. schistostelis” and “S. calias” possess similar genitalia and shell morphology, and molecular evidence suggested that they are sister taxa representing geographically isolated populations. Four new species are additionally described herein as S. furfuracea n. sp., S. pisinna n. sp., S. salweenica n. sp., and S. tonywhitteni n. sp. based on both morphology and molecular evidence. Phylogenetic analyses supported monophyly of Sophina, and further a split into two principal clades. These two clades showed little difference in genitalia, but more clear differences in the umbilical area and allopatric distribution in upper and lower reaches of the Gyaing River. High genetic divergence was revealed and this coincided with remarkable degree of endemism and localization with a pattern of one outcrop for one lineage. These data highlight the importance of the Salween Basin's karst ecosystems as an evolutionary and endemic biodiversity hotspot, and indicate that a focus on conservation and management in this area is urgently required.  相似文献   

7.
The phylogeny of all Pacific fiddler crab representatives of the subgenus Minuca Bott, 1954 (sensu Beinlich and von Hagen, 2006) is reconstructed. For the molecular analysis, Cox1 mitochondrial and 28S ribosomal nuclear DNA sequences were used. According to these data, same transisthmian sister species relationships are confirmed and a new species of the genus Uca Leach, 1814, Uca osa sp. n., is described from Golfo Dulce, a tropical gulf in Pacific Costa Rica. Morphological as well as molecular data confirm distinctness of this species compared with all other members of the subgenus Minuca, to which it belongs. Distinctive morphological traits are presented to distinguish Uca osa sp. n. from its congeners in the Eastern Pacific.  相似文献   

8.
Six new species of the Drosophila robusta species group are described from Southeast Asian Islands. Kalimantan and Sunda Islands lie east of Bali, from which Drosophila barobusta sp.nov and D. uncinata sp.nov belong to the lacertosa subgroup, and D. sungaicola sp.nov, D. baliensis sp.nov, D. hitam sp.nov and D. subaquatica sp.nov to the okadai subgroup. The robusta group from Southeast Asian tropics exclusively inhabits streamsides in mountainous highlands with an elevation of more than 600 m from the sea level.  相似文献   

9.
Baudinella Thiele, 1931, Retroterra Solem, 1985 and Molema Köhler, 2011 are three genera of camaenid land snail endemic to coastal regions of the Western Australian Kimberley. Each of these genera has fairly distinct shells, but all exhibit a rather similar configuration of the reproductive system, which is characterized by lack of a penial sheath and presence of an elongated and coiled bursa copulatrix. By combining comparative morphology of shell and penial anatomy with analyses of the mitochondrial DNA fragments 16S rRNA (16S) and cytochrome c oxidase subunit 1 (COI), the phylogenetic relationships amongst representative species of these genera are addressed to test the monophyly of taxa and to identify new species. Our results show that all three genera are members of a single camaenid radiation. Five new species are described: two new species of Baudinella, B. magna n. sp. from the Institute and Montesquieu Archipelagos and B. margaritata n. sp. from Pitta Gorge in the Prince Regent Reserve, one new species of Molema, Molema tenuicostata n. sp., from near Talbot Bay, and two new species of Retroterra, R. dichroma, and R. nana, from the Prince Regent Reserve.  相似文献   

10.

A new chigger mite Chiroptella baliensis n. sp. is described based on material from the diadem leaf-nosed bat Hipposideros diadema (Geoffroy) (Hipposideridae) in Bali Island (Lesser Sunda Islands, East Indonesia). With this newly described species, the genus Chiroptella includes 22 species, 13 in the subgenus Chiroptella Vercammen-Grandjean, 1960 (sensu stricto), and 9 in the subgenus Neosomia Vercammen-Grandjean, 1968. Species of Chiroptella are distributed throughout the Ethiopian region, the Oriental region, and the Australian region (and only marginally throughout the Palaearctic region) and are all associated with several families of bats. The paper also provides a key to all members of the genus and the new combinations for two species originally described as Chiroptella.

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11.
Two new species of the genus Plectrocnemia Stephens, Plectrocnemia levanidovae, sp. n., from Sakhalin Island and the southern Kuril Islands, and Plectrocnemia martynovae, sp. n., from southern Primorye, are described and illustrated. The new species belong to the P. tortosa Group and are the sister species of P. tortosa Banks, from China, and P. appensata Mey, from Vietnam.  相似文献   

12.
13.
Continuing the revision of the Camaenidae in the Australian Monsoon Tropics, we employed comparative analyses of morphological features (with a focus on shell and penial anatomy) and genetic markers (with a focus on mitochondrial COI and 16S sequences) to address the systematic relationships of land snails from the Victoria River District, Northern Territory, and adjacent East Kimberley (Western Australia). These analyses revealed that the species under study represented the previously undescribed genus Nanotrachia. This genus differs from all other camaenid genera known from north‐western Australia most conspicuously by its small, flat, and ribbed shell. Six species are identified as members of the new genus, four of them new species ( Nanotrachia costulata sp. nov. , Nanotrachia carinata sp. nov. , Nanotrachia coronata sp. nov. , Nanotrachia levis sp. nov. ). Two further species have already been described previously but assigned to different genera. These species, Ordtrachia intermedia (as the type species of Nanotrachia) and Mouldingia orientalis, are here transferred to Nanotrachia. Like other camaenids from the Australian Monsoon Tropics, species of Nanotrachia are characterized by essentially allopatric distributions, regional endemism, and a patchy distribution across their range. © 2013 The Linnean Society of London  相似文献   

14.
Thirteen species in four genera of mites of the family Macrochelidae phoretic on dung beetles were collected in the eastern part of the Lesser Sunda Islands, Indonesia, providing the first record of the family for that area. Of these, two species, Macrocheles entetiensis Hartini and Takaku, sp. nov. and Macrocheles sumbaensis Hartini and Takaku, sp. nov., are new to science. The remaining 11 species are Glyptholaspis fimicola, Holostaspella bifoliata, Macrocheles baliensis, Macrocheles sp. aff. glaber, M. hallidayi, M. kraepelini, M. krantzi, M. limue, M. merdarius, M. oigru and Neopodocinum sinicum.  相似文献   

15.
The land snail genus Schileykula Gittenberger, 1983 is distributed in arid limestone areas from western Turkey to north-western Iran. It comprises eight species, which display high variation in shell size and morphology. The cylindrical shells are 5–12 mm in height and the last shell whorls bear several inner lamellae and plicae. Two taxa differ in their chirality having sinistral shells, while all the others are dextrals such as the vast majority of orculids. The aim of this study was to establish a molecular genetic phylogeny of Schileykula and to test whether it conforms to the current morphology-based classification. Furthermore, we were interested in the phylogenetic position of the two sinistral forms in order to assess whether one or two reversals happened in the evolution of the genus. Nine out of ten species, including all four subspecies of Schileykula trapezensis and three of six subspecies of Schileykula scyphus, were investigated. A section of the mitochondrial cytochrome c oxidase subunit I gene was analyzed in 54 specimens of Schileykula and from a subsample, partial sequences of the mitochondrial genes for the 12S rRNA and the 16S rRNA, and a section of the nuclear H4/H3 histone gene cluster were obtained. The phylogenetic trees based on the mitochondrial sequences feature high support values for most nodes, and the species appear well differentiated from each other. The two chiral forms evolved independently and are not sister lineages. However, some groupings disagree with the present morphology-based classification and taxonomical conclusions are drawn. Schileykula trapezensis is polyphyletic in the molecular genetic trees; therefore, three of its subspecies are elevated to species level: Schileykula acampsis Hausdorf, 1996 comb. nov., Schileykula neuberti Hausdorf, 1996 comb. nov., and Schileykula contraria Neubert, 1993 comb. nov. Furthermore, Schileykula sigma is grouped within S. scyphus in the mitochondrial and nuclear trees and consequently treated as a subspecies of the latter (Schileykula scyphus sigma Hausdorf, 1996 comb. nov.). Schileykula nordsiecki, whose shell morphology is indistinguishable from that of the neighboring Schileykula scyphus lycaonica, but who differs in its genital anatomy, was confirmed to represent a distinct lineage. The phylogenies produced by the mitochondrial and nuclear data sets are to some extent conflicting. The patterns differ concerning the grouping of some specimens, suggesting at least two independent hybridization events involving S. contraria, S. scyphus and S. trapezensis. The results exemplify the importance of integrating both mitochondrial and nuclear sequence data in order to complement morphology-based taxonomy, and they provide further evidence for hybridization across distantly related lineages in land snails.  相似文献   

16.
The morphology, infraciliature, and molecular phylogeny of two novel spirotrich ciliates, Caryotricha rariseta n. sp. and Discocephalus pararotatorius n. sp., isolated from coastal waters of China, were investigated. Caryotricha rariseta n. sp. differs from its congeners mainly in possessing seven sparsely ciliated cirral rows that are conspicuously shortened posteriorly and three transverse cirri aligned in a row. Discocephalus pararotatorius n. sp. is characterized by the conspicuous spine‐like dorsal cilia, one extra (endoral?) membrane, and seven frontal, six ventral, and seven posterolateral marginal cirri. The small subunit rRNA gene was sequenced for both species. Complete SSU rRNA gene sequences of two Caryotricha spp. (including C. rariseta n. sp.) and two Discocephalus spp. (including D. pararotatorius n. sp.), along with those of 40 other ciliates, were used to determine their molecular phylogeny using maximum likelihood, neighbor joining and maximum parsimony analyses. The two Caryotricha species cluster with Kiitricha marina in the well‐supported Protohypotrichia clade that is basal to the main spirotrich assemblage. The two discocephalids form a clade that is sister to the Hypotrichia.  相似文献   

17.
We examined 12 strains representing eight species classified in the algal class Phaeothamniophyceae (Heterokontophyta). Based upon a five-gene molecular phylogeny (nuclear-encoded SSU rRNA and plastid-encoded psaA, psbA, psbC, and rbcL) and light microscopic observations, we describe five new species: Phaeoschizochlamys santosii sp. nov., Phaeoschizochlamys siveri sp. nov., Phaeothamnion wetherbeei sp. nov., Stichogloea dopii sp. nov. and Stichogloea fawleyi sp. nov. The Phaeothamniophyceae, as delimited here, form a natural group that is sister to the Aurearenophyceae. Molecular phylogenetic analyses proved more reliable than morphological characters for distinguishing species. Evolutionary trends with the SI clade of the heterokont algae are discussed.  相似文献   

18.
We herein present the first reliable record of Lepidosira from Neotropical Region. Lepidosira neotropicalis sp. n. from Brazil is described and illustrated in detail, including its complete mitochondrial genome. We perform a Bayesian phylogenetic analysis to place the new species within the Entomobryidae, and at the same time to test previous contrasting hypotheses on Lepidosira position within the Entomobryinae versus Seirinae for the first time. Phylogenetic analyses were based on one mitochondrial and two nuclear genes, Cytochrome Oxidase subunit I, 18S ribosomal RNA and 28S ribosomal RNA, respectively. Lepidosira neotropicalis sp. n. resembles L. sundana Yoshii and Suhardjono and L. nigropunctata (Nguyen) in dorsal chaetotaxy of abdominal segments I and II, but differs from all other species by the combination of head (dorsally and ventrally) and dorsal trunk chaetotaxy, plus empodial complex morphology. Our phylogenetic analyses support the placement of Lepidosira within Entomobryinae, as the sister group of Lepidocyrtoides. Overall, our revision enables a more objective diagnosis to Lepidosira and suggests that the genus is in need of a full revision due to its variable morphology, and lack of data needed to evaluate its monophyly. Finally, we provide an identification key for Neotropical genera of Entomobryinae.  相似文献   

19.
20.
Five previously described species of Dhatrichia Mosely, 1948 are recognized: D. inasa Mosely, 1948 from Yemen; D. bipunctata Statzner, 1977 from Zaire; D. lerabae (Gibon, Guenda & Coulibaly, 1994) comb. n. from Burkina Faso and Ghana; and D. cinyra Wells & Andersen, 1995 and D. divergenta Wells & Andersen, 1995 from Tanzania. A sixth species D. feredougoubae Gibon, 1987 from the Ivory Coast and Ghana is transferred to Microptila Ris, 1897 comb. n. In addition, nine new species are described and illustrated as males: D. ankasaensis sp. n., D. botiensis sp. n., D. hunukani sp. n., D. minuta sp. n., D. paraminuta sp. n. and D. wliensis sp. n. from Ghana, D. anderseni sp. n. from Tanzania, and D. madagascarensis sp. n. and D. giboni sp. n. from Madagascar. Females are associated, described and illustrated for all species, except D. inasa and D. giboni. The larvae and pupae of D. ankasaensis, D. hunukani, D. lerabae, D. minuta and D. wliensis are described and illustrated as the first known immatures of the genus. Keys to known larvae, pupae, males and females are provided. A phylogenetic analysis of the genus revealed four species groups. The most plesiomorphous taxa are West African, followed by East African and Malagasian taxa. A sister group relationship between the Eburneo–Ghanean and the Sudanian biogeographical regions is encountered twice. Among several possible sister taxa, the sister group turned out to be Kumanskiella Harris & Flint, 1992 and Microptila Ris, 1897 in part, combined. Implications for generic classification and biogeography are outlined. A morphometric principal component analysis revealed good separation of the sexes by the number and shape of antennal segments, and by eye size. Other measures are strongly dependent on overall size, and show best separation of females between species and species groups. A functional fit between male inferior appendages and secondary sexual characters in female sternite VIII is demonstrated for all species with associated females.  相似文献   

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