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1.
Spirotrichonymphea is a class of hypermastigote parabasalids defined by their spiral rows of many flagella. They are obligate hindgut symbionts of lower termites. Despite more than 100 yr of morphological and ultrastructural study, the group remains poorly characterised by molecular data and the phylogenetic positions and taxonomic validity of most genera remain in question. The genus Spirotrichonympha has been reported to inhabit several termite genera, including Reticulitermes, Coptotermes, and Hodotermopsis. The type species for this genus, Spirotrichonympha flagellata, was described from Reticulitermes lucifugus but no molecular data are yet available for this species. In this study, three new Spirotrichonympha species are described from three species of Reticulitermes. Their molecular phylogenetic position indicates that the genus is not monophyletic, as Spirotrichonympha species from Coptotermes, Paraneotermes, and Hodotermopsis branch separately. In contrast, the genus Holomastigotoides is monophyletic, as demonstrated using new sequences from Holomastigotoides species. The presence of Holomastigotoides in Prorhinotermes and the distinct phylogenetic positions of Spirotrichonympha from Reticulitermes and Coptotermes are consistent with a previously proposed symbiont fauna replacement in the ancestor of Reticulitermes.  相似文献   

2.
The ant genus Prenolepis (Hymenoptera: Formicidae) is the nominal member of the recently established Prenolepis genus‐group within the subfamily Formicinae. Our molecular phylogenetic analyses using fragments from five nuclear genes (arginine kinase, carbomoylphosphate synthase, elongation factor 1‐alpha F1, elongation factor 1‐alpha F2, wingless) and one mitochondrial gene (cytochrome oxidase I) indicate that this genus is polyphyletic. Although the majority of Prenolepis species was found to belong to the same monophyletic group (Prenolepis sensu stricto), a smaller subset of Prenolepis species, all found in either Central America or the Greater Antilles, was robustly inferred to comprise a distinct lineage that is sister to the Old World genus Paraparatrechina. Here we describe this newly discovered lineage within the larger Prenolepis genus‐group clade. The genus Zatania, gen.n. is composed of five extant species (Zatania albimaculata, Zatania cisipa, Zatania gibberosa, Zatania gloriosa, sp.n. and Zatania karstica) and one Dominican amber fossil species (Zatania electra?, sp.n. ). These are medium‐sized ants (generally between 2.5 and 3 mm in total length) that are characterized by having long scapes and legs, and elongated mesosomata. A reliance on worker‐based taxonomy has previously prevented the discovery of this new lineage because of worker convergence consisting of various combinations of elongated mesosomata, long scapes and legs, and a constriction immediately behind the pronotum, observed in several distinct lineages within the Prenolepis genus‐group. However, we did find that male morphology complements our molecular results in revealing important diagnostic and potentially phylogenetically informative characters. Our study highlights the value for ant systematics to expand beyond its traditional foundation of worker‐based morphology and embrace character systems from other castes and molecular data.  相似文献   

3.
喜雨草,湖南珍稀特有植物,属唇形科单型属喜雨草属,自1918年8月韩马迪在湖南西南部武冈云山采到模式标本,并于1936年作为一个新属、新种发表后,其踪迹消失全无。该次报道为喜雨草被发现近100年后,在湖南宁远、通道、道县、新宁被重新发现。根据采集的标本和拍摄的照片,更正修改和补充了原形态描述,重新确定了该种花萼为3/2式,花冠颜色为白色。  相似文献   

4.
Ophyra Robineau‐Desvoidy is one of the better‐studied genera of the family Muscidae (Diptera). The larvae of species of this genus feed on highly decomposed organic matter of various origins, and may reveal predatory behaviour as they mature. These feeding habits, combined with the widespread distribution and close association with human dwellings of some species, give the genus commercial and medico‐legal importance. However, the systematic position of Ophyra has been a matter of debate for many years. Ophyra has been considered by muscid workers to be either a valid genus or a junior synonym of Hydrotaea Robineau‐Desvoidy. A lack of agreement about the systematic position of Ophyra has led to serious errors, particularly in the applied literature. Recent molecular and morphological studies provided contradictory information on the validity of the genus and its subfamilial classification. We revise the systematic position of Ophyra herein by means of molecular phylogenetic reconstruction. Our results are incongruent with opinions on the systematic position of Ophyra based on previously published molecular phylogenies, although they correspond with the concept of the genus based on adult morphology. All analyses of the concatenated dataset revealed Ophyra as monophyletic and placed within a paraphyletic Azeliini. Depending on the phylogenetic approach, Ophyra was placed within either a monophyletic, paraphyletic or polyphyletic Hydrotaea, yet always closely related to a certain group of species. We conclude that Ophyra, as currently defined, should not be considered a valid name, yet a detailed reconstruction of the genus Hydrotaea awaits future studies with greater increases in both taxon sampling and the number of molecular markers.  相似文献   

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8.
Kanouh, M., Tixier, M.‐S., Okassa, M. & Kreiter, S. (2010). Phylogenetic and biogeographic analysis of the genus Phytoseiulus (Acari: Phytoseiidae) —Zoologica Scripta, 39, 450–461. The taxonomy of the genus Phytoseiulus (sub‐family Amblyseiinae), has a tumultuous and confused history. This genus currently contains four species, but in previous revisions it contained five, sometimes grouped in two genera. There are no thorough phylogenetic analyses available for the group, analyses against which taxonomic and evolutionary hypotheses could be tested. The present study aims to apply morphological and molecular data to determine phylogenetic relationships among the four species presently included in this genus plus Afroseiulus robertsi, which was previously included in this genus. The new analyses show that the species of the genus Phytoseiulus do not constitute a monophyletic group. A delineation between (i) P. macropilis, P. persimilis, P. fragariae and (ii) P. longipes and A. robertsi is observed. Biogeographic data sets showed that the Neotropical and Afrotropical regions contain the highest diversity of species of Phytoseiulus and of their host plants. Consequently, the western part of Gondwana is hypothesized to be the probable centre of origin for this taxon.  相似文献   

9.
The freshwater flatworm genus Schmidtea is endemic in the Western Palearctic region, where it is represented by only four species, thus contrasting with the high species diversity of the closely related genus Dugesia within Europe. Although containing an important model species in developmental and regeneration research, viz. Schmidtea mediterranea, no evolutionary studies on the genus Schmidtea have been undertaken. For the first time, we present a well‐resolved molecular phylogenetic tree of the four species of the genus, inferred on the basis of two molecular markers, and provide also the first detailed morphological account of Schmidtea nova. The phylogenetic tree generated corroborates an earlier speciation hypothesis based on karyological data and points to chromosomal rearrangements as the main drivers of speciation in this genus. The high genetic divergence between the four species, in combination with previous dating studies and their current geographic distribution, suggests that Schmidtea could have originated in Laurasia but lost most of its diversity during the Oligocene. Thus, its present distribution pattern may be the result of the expansion of three of its four relictual species over Europe, probably after the Pleistocene glaciations. Our detailed morphological study of S. nova revealed that it shows a number of remarkable features: interconnected testis follicles, parovaria, an ejaculatory duct exiting into the primary as well as the secondary seminal vesicle by means of a nipple, and the wall of the distal section of the ejaculatory duct being sclerotic or chitinized.  相似文献   

10.
The history of the Quaternary genus Didacna, which is endemic to the Ponto-Caspian Sea, is discussed. Quaternary stratigraphy of this region and Didacna assemblages recorded in the Neopleistocene sequence are characterized. The development of this genus against the background of the Ponto-Caspian history is reconstructed; the replacement of species and associations of Didacna, the character of speciation, and examples of homeomorphism are discussed. Seventy-seven species of this genus, which appeared over slightly more than 600 thousand years, are described; this indicates an extremely intense speciation in Pleistocene brackish-water basins, which were inhabited by only five bivalve genera belonging to two families.  相似文献   

11.
Ctenogobiops is a genus of Indo-Pacific gobies that form obligate, mutualistic associations with shrimp in the genus Alpheus. This study provides a molecular phylogenetic analysis of eight Ctenogobiops species: C. aurocingulus, C. crocineus, C. feroculus, C. formosa, C. maculosus, C. mitodes, C. tangaroai, and C. tongaensis. We recover two clades within the genus, one consisting of C. feroculus and C. aurocingulus, the second including the remaining species arrayed as follows: (C. tongaensis (C. mitodes (C. formosa (C. maculosus (C. crocineus, C. tangaroai))))). Recovery of C. maculosus and C. crocineus as distinct taxa suggests that these species are not synonymous, although sampling in this study is limited. Species of Ctenogobiops are morphologically very similar to each other, with generally consistent meristic character states present throughout the genus. Recognition of species is based primarily on slight variations in color pattern, shape of the dorsal fin, and size of the gill opening. Comparison of our specimens of C. mitodes with accounts of C. pomastictus confirms that color pattern variations and lateral scale counts are more reliable indicators of species identity than relative dorsal fin spine length, particularly for smaller specimens. We evaluate the distribution of morphological characters in the context of the new phylogenetic hypothesis, and provide a summary of distinguishing characters for Ctenogobiops species. In this case, as in other instances of diverse reef-dwelling fish taxa, molecular data are ideal for inferring phylogenetic relationships, whereas morphological data remain the most expedient way to identify species.  相似文献   

12.
Thraustochytrium is the type genus of the family Thraustochytriaceae in the class Labyrinthulomycetes. This genus is characterized by zoospore formation, namely, shape of the cell wall of sporangia and presence or absence of a proliferous body. However, there are several issues associated with the taxonomy of this genus, and these include polyphyletic taxa and overlapping of taxonomic features among species. In particular, the first and second species, T. proliferum and T. globosum, were described based on observations of the morphological features of natural samples in the absence of culture conditions. Before addressing the taxonomic issues associated with this genus, it is important to consider the taxonomic features of each species, i.e., the life history under culture conditions and the phylogenetic position. The objective of the present study was to isolate T. globosum, the second described species in the genus Thraustochytrium, from the type locality. We successfully isolated strain NBRC 112723, which exhibited characteristic features of T. globosum. Under culture conditions, strain NBRC 112723 exhibited taxonomic features observed in other thraustochytrid species. Our molecular phylogeny indicated that this strain isolated from the type locality was located in an unidentified thraustochytrid group; moreover, some strains located in this group exhibited characteristic features of strain NBRC 112723. We clearly distinguished T. globosum based on the taxonomic criteria used to classify the T. proliferum type species. Therefore, we propose the establishment of a new genus, Monorhizochytrium, for the species T. globosum in the family Thraustochytriaceae.  相似文献   

13.
Species of Homoeoxipha are very small and always live on leaves of shrubs and grasses. This genus contains ten species worldwide and is distributed across five zoological regions, from Africa to New Guinea. Homoeoxipha lycoides is the type species of this genus and possesses the characteristic coloration for the genus. These coloration features resulted in some synonyms and disputes over species, because most Homoeoxipha species are ornamented with a similar coloration pattern. We compared and documented the differences between H. lycoides and its relatives in China. A new important character, the epiphallic transversal suture, is used to distinguish them. Based on this work, all of the Chinese species, H. lycoides, H. obliterata and H. nigripes, and one new species, H. eurylobus, with similar coloration to H. lycoides, are described and illustrated.  相似文献   

14.
Martinsson, S., Kjærandsen, J. & Sundberg, P. (2011). Towards a molecular phylogeny of the fungus gnat genus Boletina (Diptera: Mycetophilidae). —Zoologica Scripta, 40, 272–281. Boletina is a species rich genus of fungus gnats (Diptera: Mycetophilidae) with a mainly Holarctic distribution. The systematics within the genus has gained little attention and this is a first attempt to shed some light over the systematics of Boletina and to test the segregation of the genera Saigusaia and Aglaomyia from Boletina. The nuclear marker 28S and mitochondrial 16S, COI and CytB were amplified and sequenced for 23 taxa that were analysed separately and together with a broad sample of outgroup taxa obtained from GenBank, where also 18S sequences were added. Phylogenies were estimated using maximum likelihood, Bayesian inference and parsimony. We strengthen the hypothesized sister‐group relationship between Docosia and Boletina, but the genus Boletina as currently delimited appears to be paraphyletic and nested in a clade together with Aglaomyia, Coelosia and Gnoriste. The genus Saigusaia, on the other hand, seems to be well separated from Boletina. The Boletina erythropyga species group is consistently found as a distinct basal clade within Boletina s.l. The results obtained are otherwise ambiguous both for the taxa in focus and in some analyses globally with a statistically supported total breakdown of the traditional higher classification into tribes, subfamilies and even families. Interestingly, this breakdown almost disappeared when additional 18S sequences were added.  相似文献   

15.
The current taxonomy on the haemococcidia establishes that the two genera of protozoan parasites that integrate the family Lankesterellidae are Lankesterella and Schellackia. However, the phylogeny of these genera, as well as the other coccidia, remains unresolved. In this sense, the use of type and described species is essential for the resolution of systematic conflicts. In this study, we molecularly characterize the type species of the genus Schellackia, that is, S. bolivari from Europe and also a described species of the same genus from Asia. At the same time, we contribute with the molecular characterization of another species of the genus Lankesterella. All this put together supports the polyphyly of the family Lankesterellidae. Therefore, we propose the resurrection of the zoological family, Schellackiidae Grassé 1953 , to include species within the genus Schellackia.  相似文献   

16.
Introduction of non-native fish species has been criticized as one of the major threats to freshwater ecosystems. During recent years, the cyprinid fish genus Carassius has been the subject of various studies in terms of introduction biology and ecology. The taxonomy and identification of described species in the genus Carassius is still ambiguous. In order to increase the knowledge of introduced species of the genus in Iran, molecular approaches were employed to identify species based on the mitochondrial gene, cytochrome b (Cyt b). In total, 417 specimens across Eurasia and some other parts of the world have been analyzed. Afterwards, investigation of the possible origin and pathways of introduction was done using analysis of haplotype networks based on the Cyt b gene. The results revealed that there are three introduced species i.e., Carassius auratus, Carassius gibelio and Carassius langsdorfii, in inland waters of Iran. Carassius langsdorfii was recorded from Iran and western Asia for the first time. Analysis of haplotype network showed various potential sources of introduction for each species in Iran and regions beyond their native distribution ranges.  相似文献   

17.
A set of six cloned barley (Hordeum vulgare) repetitive DNA sequences was used for the analysis of phylogenetic relationships among 31 species (46 taxa) of the genus Hordeum, using molecular hybridization techniques. in situ hybridization experiments showed dispersed organization of the sequences over all chromosomes of H. vulgare and the wild barley species H. bulbosum, H. marinum and H. murinum. Southern blot hybridization revealed different levels of polymorphism among barley species and the RFLP data were used to generate a phylogenetic tree for the genus Hordeum. Our data are in a good agreement with the classification system which suggests the division of the genus into four major groups, containing the genomes I, X, Y, and H. However, our investigation also supports previous molecular studies of barley species where the unique position of H. bulbosum has been pointed out. In our experiments, H. bulbosum generally had hybridization patterns different from those of H. vulgare, although both carry the I genome. Based on our results we present a hypothesis concerning the possible origin and phylogeny of the polyploid barley species H. secalinum, H. depressum and the H. brachyantherum complex.  相似文献   

18.
The caenogastropod family Littorinidae is almost exclusively marine, but a unique freshwater genus, Cremnoconchus, is known from India. Its members are restricted to montane streams on the western escarpment of the Western Ghats, at altitudes between 300 and 1400 m. Four species and several varieties were described in the 19th century, but no taxonomic study has been carried out for over 120 years and the last anatomical report was in 1935. Nevertheless, they are of unusual evolutionary interest and also of conservation concern as a genus endemic to the Western Ghats biodiversity hotspot. Based on anatomical study of newly collected material and examination of historical and type specimens, we present a systematic revision of Cremnoconchus, illustrating shells, radulae, and reproductive anatomy. The very large eggs, invaginated penial filament, and calcified operculum are unique among Littorinidae. Three valid, described species (C. syhadrensis, C. conicus, C. canaliculatus) are recognized in the northern Western Ghats in Maharashtra state, where all can occasionally be found sympatrically. We describe an additional six new species from the central Western Ghats in a small area (linear distance 80 km) of Karnataka state, over 500 km south of the previously known range of the genus. Here the species each appear to be restricted to a single drainage system. Because of their highly restricted distribution and fragile habitat, this radiation of nine species is judged to be endangered. © 2013 The Linnean Society of London  相似文献   

19.
The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South‐West Pacific is a biodiversity hot spot for these squat lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of squat lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 465–493.  相似文献   

20.
A new species of the genus Salganea is described from Mount Victoria, Chin State, Myanmar under the name of Salganea matsumotoi sp. nov. Morphological investigation suggests that this species belongs to the S. nigrita species group. The inferred molecular phylogenetic tree indicates that S. matsumotoi is most closely related to the taxa S. incerta, S. taiwanensis, S. gressiti and S. esakii, distributed in Thailand, Taiwan and Japan, all of which belong to the S. nigrita species group. Social structural data suggest that this species is subsocial, and in contrast to other studied species in the genus, potentially has more than one reproductive episode.  相似文献   

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