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1.
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Hemiodus iratapuru, a new species of the Hemiodontidae from the Rio Iratapuru, a left bank tributary of the Rio Jari, Amazon Basin, Brazil, is described. The new species is diagnosed from other species of Hemiodus by modifications in the ectopterygoid, tooth form, scale counts, dorsal‐fin form and colour pattern. The new species is proposed to be related to the Hemiodus quadrimaculatus species group.  相似文献   

3.
Tetrahymena mitochondrial cox1 barcodes and nuclear SSUrRNA sequences are particularly effective at distinguishing among its many cryptic species. In a project to learn more about Tetrahymena natural history, the majority of >1,000 Tetrahymena‐like fresh water isolates were assigned to established Tetrahymena species with the remaining assigned to 37 new species of Tetrahymena, nine new species of Dexiostoma and 12 new species of Glaucoma. Phylogenetically, all but three Tetrahymena species belong to the well‐established “australis” or “borealis” clades; the minority forms a divergent “paravorax” clade. Most Tetrahymena species are micronucleate, but others are exclusively amicronucleate. The self‐splicing intron of the LSUrRNA precursor is absent in Dexiostoma and Glaucoma and was likely acquired subsequent to the “australis/borealis” split; in some instances, its sequence is diagnostic of species. Tetrahymena americanis, T. elliotti, T. gruchyi n. sp., and T. borealis, together accounted for >50% of isolates, consistent with previous findings for established species. The biogeographic range of species found previously in Austria, China, and Pakistan was extended to the Nearctic; some species show evidence of population structure consistent with endemism. Most species were most frequently collected from ponds or lakes, while others, particularly Dexiostoma species, were collected most often from streams or rivers. The results suggest that perhaps hundreds of species remain to be discovered, particularly if collecting is global and includes hosts of parasitic forms.  相似文献   

4.
ABSTRACT

Aegilops L. includes wild species from which, over millennia, man has cultivated forms of Triticum L. Ten species of Aegilops occur in Italy. Three species are allochthonous and eight out of ten species are recorded in the Apulia region. Five out of the ten species have been included in Red Lists. Each taxon is presented and discussed, citing old and new sites of occurrence, by examining specimens from many different herbaria, and describing their ecology and habitats, according to the Directive 92/43 EEC. A new taxonomic key, for the identification of all Aegilops species growing in Italy, is provided. The occurrence of Aegilops caudata L., A. peregrina (Hack. in J. Fraser) Maire & Weiller and A. speltoides Tausch in Italy is doubtful.  相似文献   

5.
Chromosomes,DNA sequences,and evolution in salamanders of the genus Aneides   总被引:1,自引:1,他引:0  
Chromosomes and DNA sequence homologies have been studied in salamanders of the genus Aneides. The species studied included A. ferreus, flavipunctatus, lugubris, hardii and aeneus. All species have 14 chromosomes. The karyotypes of A. ferreus and A. hardii are very similar. All chromosomes are metacentric or sub-metacentric except chromosome 13 which is telocentric in A. hardii, but is represented by a telocentric and a sub-telocentric chromosome in A. ferreus. C values range from 35.2 to 46.0 pg. Salamanders from different species groups have nothing in common with respect to that fraction of their repeated DNA sequences that hybridizes in experiments involving the binding of labelled whole complementary RNA from one species to whole DNA from another species. Salamanders from the same species group (ferreus, lugubris and flavipunctatus) have about 25% in common with respect to their repetitive DNA sequences.  相似文献   

6.
Among four different genera in Galaxauraceae, species diversity of the genus Tricleocarpa Huisman & Borowitzka is underestimated and requires further examination. In this study, we explored a molecular phylogeny of Tricleocarpa with an emphasis on Taiwan species and reassessed species diversity of the genus from the Indo-Pacific region based on analyses of rbcL and COI-5P sequences and morphological observations. The molecular analyses showed that species of Tricleocarpa examined are grouped into seven clades: six clades in the T. cylindrica group (the T. cylindrica complex, T. confertus, T. jejuensis, T. natalensis and two uncharacterized T. ‘cylindrica’ clades) and one clade as the T. fragilis group. Overall, at least 12 species in Tricleocarpa were detected from the Indo-Pacific region, including a new species, T. confertus S.-L. Liu & S.-M. Lin, from Taiwan. Among them, T. confertus can be separated from other species of Tricleocarpa by a thallus consisting of dichotomous or trichotomous, articulated and moniliform branches with smooth surfaces, constrictions at nodes and slightly anti-triangular in shape. The cystocarp morphology of T. confertus is similar to the T. cylindrica group by having paraphyses intermixing with gonimoblast filaments. Recognition of this new species from other species is also supported by the DNA-based, algorithmic species delimitation approaches. With the combination of molecular phylogeny and species diversity reassessment, our phylogeographic analysis supported a trend that species in the T. fragilis group are restricted in their distribution to subtropical and tropical areas whereas species in the T. cylindrica group have a wide distribution, ranging from temperate through to tropical areas.  相似文献   

7.
A new loach Oreonectes guilinensis sp. nov. is described from Guangxi Zhuang Autonomous Region, China. It is the second surface-dwelling fish identified in the genus Oreonectes after the type species Oreonectes platycephalus. This new species can be distinguished from other species within the genus by the combination of the following features: a round caudal fin, 13–14 branched rays, an incomplete lateral line with 4–6 pores, a short pelvic fin located some distance from the anus, a scale-covered body, a stout build (body width 14.0%–16.7% of standard length), a posterior chamber of well-developed airbladder and a yellowish-brown body with a lateral dark brown strip. The maximum likelihood phylogenetic analysis based on cytb gene recovered this new species in a well-supported clade with the type species O. platycephalus, sister to the Lefua clade. Morphological comparisons as well as our phylogenetic tree support Oreonectes shuilongensis, Oreonectes daqikongensis, Oreonectes jiarongensis as species of Troglonectes. Based on our results there are 6 valid species in the genus Oreonectes.  相似文献   

8.
Several species of the family Petraliellidae were first described from the coast of Queensland, including the type species of Sinupetraliella, S. litoralis. These species are redescribed from type, or topotype specimens, and include Petraliella concinna, which has not been certainly found since its introduction in 1891; lectotype material is designated for P. buski and P. magna. Six other species are described from Queensland, P. crassocirca, P. dentilabris, P. dorsiporosa, Mucropetraliella bennetti, M. serrata and M. tuberosa. The species Mucropetraliella tuberosa is a new addition to the Queensland fauna and is described and illustrated here for the first time since its introduction in 1884. The characters of the family Petraliellidae are briefly discussed and the genera to which the Queensland species are assigned is reviewed. A taxonomic key to the ten Queensland petraliellid species described is also provided.  相似文献   

9.
10.
The vine weevil Otiorhynchus sulcatus is a parthenogenetic reproducing species which forages for suitable host plants at night, but is found congregated in dark places during the day. Frass of this weevil species is suspected to contain attractive compounds that are host‐plant related. Using a still‐air olfactometer, we tested adult vine weevils at night for their behavioural response to odours from conspecifics, feeding on a mixture of spindle tree (Euonymus fortunei) and yew (Taxus baccata), and to a sexually reproducing related species (Otiorhynchus salicicola), feeding on a mixture of ivy (Hedera helix) and cherry laurel (Prunus laurocerasus). Their attraction to conspecifics and O. salicicola appeared to be related to frass production. Freshly collected frass from O. sulcatus and from O. salicicola males and females was attractive. Prunus laurocerasus and H. helix have not been observed to be hosts of the vine weevil in the field. However, our tests showed that the vine weevil was attracted to mechanically damaged leaves of both plant species, whereas undamaged leaves were not attractive. Only undamaged young unfolding leaves of H. helix were also attractive. The attraction to odours from mechanically damaged host and non‐host plants suggested the involvement of compounds that are commonly found in many plant species. The involvement of plant compounds and/or aggregation pheromones in attraction to frass of the vine weevil and frass of the related weevil species O. salicicola is discussed.  相似文献   

11.
About 50 species in more than 20 genera of the microdrile oligochaete families Tubificidae, Naididae, Opistocystidae, and Enchytraeidae and the freshwater megadrile families Sparganophilidae and Alluroididae were identified in recent collections made in Guyana. Only seven species in these families were previously recorded from Guyana. The aquatic oligochaete fauna has similar components to those of the southeastern United States, other locations in South America, and across lower latitudes in the northern hemisphere. A high diversity of species is found in the naidids especially in the genera Pristina and Pristinella, especially considering the small number of locations that have been sampled. The collections include approximately 12 new species of rhyacodrilines (Tubificidae), Dero, Pristina, Pristinella (Naididae), Brinkhurstia (Alluroididae), Hemienchytraeus and Aspidodrilus (Enchytraeidae). This is the first record of Aspidodrilus from outside of Africa and the first new record since 1952.  相似文献   

12.
Cinereomyces clade is a newly proposed monophyletic group of polypores containing currently four genera and five species, including two promising biopulping fungi, Ceriporiopsis rivulosa and C. subvermispora. The Cinereomyces clade is well-delimited in nrDNA-based phylogenetic analysis, but its position in Polyporales remains unclear. Its closest relative may be found in the core polyporoid clade. Only a few morphological characters are common for all the species in the clade, e.g. CB– and CRB+ hyphae, white fruiting bodies, presence of oil, and middle-sized spores. Culturally, the species are unified by producing simple-septate generative hyhpae in the margin, which produce simple-clamped hyphae backwards. The genus Gelatoporia is the correct place for Ceriporiopsis subvermispora. Two new genera are described in the group: Obba to incorporate C. rivulosa and a new austral species, Obba valdiviana, known from southern Argentina and recorded here also from Tasmania, and Sebipora to accommodate a new species from tropical Asia, S. aquosa. ITS sequences imply that Eurasian Gelatoporia subvermispora may belong to a different species from the North American one. G. subvermispora is recorded as new to Indonesia.  相似文献   

13.
The genus Hemistola Warren from China is reviewed, and seven new species are described: H. viridimargo, sp. nov., H. glauca sp. nov., H. asymmetra sp. nov., H. arcilinea sp. nov., H. flavifimbria sp. nov., H. orbiculosoides sp. nov. and H. stueningi sp. nov. Two species, acyra and christinaria, are transferred from Hemistola to Maxates and Comostola, respectively: Maxates acyra comb. nov. and Comostola christinaria comb. nov. Including the 25 species previously known from China, a total of 32 species is now recorded. All Chinese species are redescribed. Generic characters based on all species are summarized. Illustrations of adults and genitalia are presented.  相似文献   

14.
The Napaeus variatus (Webb & Berthelot, 1833) species group from the Canary Islands is reviewed from literature information, types, other museum specimens, and newly collected material. Anatomy data is newly provided for six species. Five new species are described: N. elegans and N. esbeltus from Tenerife, N. orientalis and N. beguirae from La Gomera, and N. exilis from Gran Canaria. Eight species lack a diverticulum and are referred to the subgenus Napaeus (Napaeus) Albers, 1850, whereas five species are provided with a diverticulum and arc referred to Napaeus (Napaeinus) Hesse, 1933. Four species cannot be assigned to a subgenus due to a lack of information. Keys of species from the different islands are provided.  相似文献   

15.
Barnacles of the genus Galkinius occupy a large spectrum of host corals, making it one of the least host‐specific genera within the Pyrgomatidae. Molecular analyses show that within the genus Galkinius there are highly supported clades, suggesting that the genus Galkinius is a complex of evolutionarily significant units (ESUs). The morphology of the opercular valves has been used as the basis for the separation of species of Galkinius. In this study, morphological variability was found both between specimens within ESUs extracted from different host species and between specimens extracted from the same colony. Identifications based on the opercular valves cannot therefore be assigned to different species despite being genetically distinguishable. It is proposed that in many cases the differences between valve morphology of different species of Galkinius are the outcome of ontogeny. Allometric growth of the valves has resulted in differences in the proportions of the parts of the valve. © 2015 The Linnean Society of London  相似文献   

16.

The cosmopolitan subfamilies Aphrodinae, Jassinae, Xestocephalinae, Idiocerinae, and Macropsinae are diagnosed and the New Zealand species described and illustrated. Each subfamily is represented in New Zealand by only one or two species, those in Idiocerinae having been introduced from Europe or North America. The species Euacanthella brunnea Evans (Aphrodinae) is synonymised with the Australian species E. insularis Evans (new synonymy).  相似文献   

17.
Scanning electron microscopy and transmitted light microscopy are used in a palynological study of Lophosoria, Metaxya, Sphaeropteris, Alsophila, and Nephelea of the tree fern family Cyatheaceae. The monotypic American genera Lophosoria and Metaxya each have a unique spore morphology which reinforces the taxonomic distinctness of these genera as indicated by their other characters. All investigated paleotropical species of Sphaeropteris develop a single type of perine characterized by coarse, pointed projections. In the neotropics, the Sphaeropteris horrida group shares this perine type, whereas all other neotropical Sphaeropteris species appear to have a different kind of perine with fine hair-like processes. The exine in paleotropical Sphaeropteris appears uniformly unsculptured, whereas in the neotropics several exine morphologies are found. In Alsophila all investigated neotropical species and the vast majority of the paleotropical species are characterized by a basically ridged perine morphology and an unsculptured exine. In several paleotropical Alsophila species, however, a perine with hair-like processes similar to those in neotropical Sphaeropteris is found, and the exine in several species is variously pitted. In at least one paleotropical Alsophila species, the porate exine morphology is indistinguishable from that in the neotropical genus Cnemidaria. The spores of the American genus Nephelea are similar to those of the majority of Alsophila species in ridged perine morphology and unsculptured exine. Several new instances of atypical spore numbers per sporangium are reported in Sphaeropteris and Alsophila. These and the palynological data are discussed in a taxonomic framework. The spore morphology in these genera is consistent with Tryon's recent generic revision of the family.  相似文献   

18.
《Journal of bryology》2013,35(3):161-164
Abstract

The genus Lobatiriccardia Furuki is reported as new to China, from the Dulong River valley, Gaoligong Shan range, Yunnan Province and this material is described as a new species endemic to China, Lobatiriccardia yunnanensis Furuki & D.G. Long, the fifth known species in the genus. The differences between the new species and the other members of the genus are enumerated, along with a key to all known species of Lobatiriccardia.  相似文献   

19.
20.
Snub-nosed monkeys (Rhinopithecus spp.) are confined to isolated mountainous regions in China and North Vietnam. Their systematic classification and phylogenetic relationship has been controversial. The structures of mitochondrial DNA cytochrome b and 12S rRNA show that the 4 species of Rhinopithecus are quite different from other colobines. It is reasonable to regard them as an independent genus, as determined by external features, morphometric characters and behavior. However, whether or not there should be a subdivision between the Vietnamese and Chinese species at the subgeneric level remains to be clarified; more evidence from a large range of Asian colobine species is needed. The Guizhou species, Rhinopithecus brelichi, is a valid species, which is more closely related to Pygathrix than the other species ( R. roxellana, R. bieti and R. avunculus) are. Results also indicate that 3 species—Rhinopithecus roxellana, R. bieti and R. avunculus—might have diverged from R. brelichi, but the phylogenetic relationship of R. avunculus is not clear.  相似文献   

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