首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
Pseudophoxinus turani sp. n. is described from the İncesu Spring (Hassa-Hatay) drainage of Asi River, Turkey. It is distinguished from other Eastern Mediterranean Region Pseudophoxinus species by a combination of characters: lateral line incomplete, with 12–25 (commonly 16–21) perforated scales and 38–46+2-3 scales in lateral series (commonly 41–44+2-3); 10–11 scale rows between the lateral line and dorsal-fin origin; 3–4 scale rows between the lateral line and the pelvic–fin origin; dorsal fin with 7½ branched rays; anal fin commonly with 7½ branched rays; 8-11gill rakers on the first branchial arch; dorsal profile markedly convex with marked hump at the nape, ventral profile less convex than dorsal profile; a small, irregular, black blotch on the base of the caudal fin; mouth terminal, with slightly distinct chin, its corner not reaching vertical through anterior margin of eye; snout somewhat long, with rounded tip; and its length greater than eye diameter.  相似文献   

3.
王子彤  张鹗 《生物多样性》2021,29(9):1256-30
赣江是长江的主要支流之一, 淡水鱼类多样性极其丰富, 但是目前对于该河流的鱼类多样性还未有充分的了解。本研究于2016年9月至2017年8月对赣江鱼类进行了实地调查, 结合历史文献资料并参考最新的分类学成果, 更新了赣江淡水鱼类名录。结果表明, 赣江共有淡水鱼类180种, 隶属于12目31科93属。其中, 土著鱼类174种, 外来鱼类6种。赣江鱼类以鲤形目为主; 鲤科种类最多, 其次是鲿科。更新的物种名录中, 包含23个新记录土著种, 其中有5个未被描述的新种; 有36个历史资料记载的种类被剔除出物种名录; 25个物种发生了分类地位的变更。此外, 本次调查有28种鱼类未采集到, 说明这些鱼类的种群数量正在急剧下降, 而这些鱼类分别属于洄游性、流水性和产漂流性卵等独特生态类型, 说明赣江鱼类多样性受到了严重的人为干扰。本研究所给出的赣江鱼类的更新物种名录, 可为今后的赣江鱼类多样性保护提供理论基础。  相似文献   

4.
5.
6.
The genera of the insect parasitic nematode family Mermithidae axe reviewed, and 16 of them axe redescribed and illustrated. Information is given on methods of rearing adult mermithid specimens and on host specificity. The four types of merrnithid life cycles axe described in detail. One figure shows the variety of insects parasitized by merrnithids and the location and size of the nematode within the insect. Several mermithid eggs are illustrated, and their usefulness in identification is discussed.Taxonomically, the primary emphasis is on the adult stages of the merrnithJds with larval and egg characteristics supplementaxy. An emended family diagnosis is given. Merrnis subnigrescens is considered a synonym of M. nigrescens, and M. tahitiensis is synonymized with M. mirabilis. Hydromermis contorta is accepted, leaving the genus Paramermis in an uncertain position. Study of the Steiner collections of Limnornermis bathybia indicates that Limnornerrnis is accepted as a valid genus. The adults of Agamermis decaudata are descried and illustrated for the first time. The genus Gastromermis is limited to the long single-spiculed forms, as it is now apparent that five or more genera have ventrally shifted mouth orifices. Amphirnermis tinyi n. sp. is described from damselflies from Louisiana. The genus Lanceimermis is accepted, and three species in this genus are illustrated. The taxon Reesimermis nielseni has been accepted for this important parasite of more than 20 mosquito species. This nematode previously has been referred to as Romanomermis sp. Romanomermis iyengari is transferred to the genus Reesirnermis. Diximermis peterseni n. gen., n. sp., from anopheline mosquitoes, is described and iUustrated. The adults of Agamomermis culicis which parasitize Aedes sollicitans, are described for the first time, and the species placed in a new genus, Perutilimermis. The new genus Neornesornermis is proposed for Mesomermis flumenalis Welch, 1962. Several problems on mermithid morphology and taxonomy are discussed. Type material is established for some of the taxa.  相似文献   

7.
Salmo fahrettini, a new species, is distributed in the northern tributaries of the Euphrates River. It differs from other Salmo species in adjacent waters by a combination of the following characters: a greyish body; one black spot behind the eye and on the cheek; three to six black spots on the opercle; numerous black spots on the back (missing on the predorsal area), flank and middle part of body, surrounded by a roundish white ring; red spots in the median part of the body, surrounded by a roundish white ring; short and narrow maxilla; increase in the number of black and red spots with an increase in size; adipose fin medium size, no or rarely one red spot at its posterior edge; 109–116 lateral line scales; 27–30 scale rows between dorsal-fin origin and lateral line; 20–23 scale rows between the lateral line and anal-fin origin; maxilla length 8.8–10.0% standard length in males, 8.8–9.6 in females.  相似文献   

8.
In a study of the fishes of the Euphrates River (Persian Gulf basin) three species of Squalius belonging to the cephalus-group were found: The Tohma population was identified as S. seyhanensis and the Merzimen and Hilvan populations as S. berak. The comparison of 28 metric and 5 meristic parameters and morphological characters showed that the populations of the northern Euphrates River drainages are distinct and belong to a hitherto unnamed species. We describe it here as Squalius semae sp. n.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:D195B69C-C6CB-4DEB-B85D-5B695F917CE5  相似文献   


9.
This study aimed to estimate the parameters of length-weight relationships (LWRs) for six freshwater fish species that inhabit in the Xiangjiang River of Guangxi region, China. The specimens were sampled in April, July, and October 2014 and in January 2015 using electrofishing (CWB-2000P, China; 12 V import, 250 V export) and traps (mesh size 8.5 mm; length 200 m) at five sampling sites. For each sampling site, a trap was settled on one nearshore zone of the river for 24 hr, and the electrofishing was applied within 30 min from downstream to upstream with 200 m long. Standard length was measured (be accurate to 0.1 cm) and total weight determined (be accurate to 0.1 g) after preservation in formaldehyde (10%). The values for the parameter b of the length-weight relationships were estimated together with the coefficient of determination scores. In addition, this study provides a new tentative LWRs for the six species.  相似文献   

10.
11.
Nineteen species of seed-beetles belonging to the subfamily Bruchinae (Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the following four were new records for China: Bruchus affinis Frolich, 1799, Bruchus atomarius L., 1761, Bruchus loti Paykull, 1800 and Kytorhinus kergoati Delobel & Legalov, 2009. We provide an annotated checklist, illustrations and a key to the 19 species.  相似文献   

12.
We describe two new species of springsnails (genus Pyrgulopsis) for populations from the middle Fork and upper East Fork of the Gila River Basin (New Mexico) that had been previously identified as P. gilae. We also restrict P. gilae to its originally circumscribed geographic range which consists of a short reach of the East Fork Gila River and a single spring along the Gila River (below the East Fork confluence). These three species form genetically distinct lineages that differ from each other by 3.9–6.3% for mtCOI and 3.7–8.7% for mtNDI (the latter data were newly obtained for this study), and are diagnosable by shell and penial characters. Collectively the three species form a strongly supported clade that is distinguished from other congeners by the unique presence of two glandular strips on the dorsal surface of the penial filament. These findings suggest that the conservation status of P. gilae, which was recently removed from the list of candidates for listing as endangered or threatened by the United States Fish and Wildlife Service, should be revisited and that the two new species may also merit protective measures given their narrow geographic ranges.  相似文献   

13.
Ray Gibson  Qi Sang 《Hydrobiologia》1991,220(2):167-178
A new genus and species of freshwater heteronemertean, Amniclineus zhujiangensis, from the Zhujiang (Pearl River), People's Republic of China, is described and illustrated. The species is placed in the family Lineidae along with the existing freshwater heteronemertean taxa, with which its anatomy is compared.  相似文献   

14.
The characters of the genitalia of the females of Glyptotendipes glaucus (Meigen, 1818), Glyptotendipes pallens (Meigen, 1804), Glyptotendipes paripes (Edwards, 1929), Glyptotendipes gripekoveni (Kieffer, 1913), Glyptotendipes aequalis (Kieffer, 1922), Glyptotendipes barbipes (Staeger, 1839) and Glyptotendipes salinus Michailova, 1987 are described. A key for the identification of these species is given.The taxonomic status of Glyptotendipes aequalis is discussed.  相似文献   

15.
A new species of Hemigrammus is described from the Amazon Basin near Leticia, Departamento Amazonas, Colombia. In common with some congeners and some Hyphessobrycon spp., the new species colour pattern lacks a humeral blotch but has a caudal-peduncle blotch. It can be distinguished from congeners with a similar colour pattern by having: a relatively deep body (30.2%–39.0% LS), 20–24 branched anal-fin rays, 6–8 perforated scales of the lateral line, anal-fin base without a conspicuous black stripe, 3–5 maxillary teeth, maxillary teeth with 1–3 cusps, a thin longitudinal midlateral line and a well-defined oval shaped caudal blotch, extending from caudal peduncle into the lower caudal-fin rays. Comparisons with congeners and with Hyphessobrycon species sharing the same general colour pattern are presented.  相似文献   

16.
17.
18.
The population dynamics of trout (Salmo trutta L.) were studied in two high-altitude streams flowing westwards into the River Eden in northern England. The results from one (Knock Ore Gill), which is accessible to spawners from downstream, were compared with published data from an isolated population in a nearby stream which flows eastward into the River Tees. The Knock Ore Gill trout had a population density of 0.4–0.9 fish m–2, a biomass of 12.4 g m–2, annual production of 12–14 g m–2 year–1 and an instantaneous mortality rate of 0.97 year–1. Comparable values from the Tees tributary were 0.2, 3.3, 2.3 and 0.66 respectively. The Knock Ore Gill population also contrasted with that of the Tees tributary in having reliable recruitment from year to year. These differences were related to differences in the chemistry and spate characteristics of the two streams and to the fact that immigrants from downstream were responsible for over 30% of the annual oviposition in Knock Ore Gill.  相似文献   

19.
Chrysobrycon mojicai sp. nov. is described from forest streams that are part of the Amazon River basin in Colombia. It is distinguished from all congeners by having most of the maxillary teeth with distal tips lateroventrally curved (v. teeth straight along their lengths) and a greater number of dentary teeth (20–27 v. 11–19, except in Chrysobrycon yoliae). The posterior margin of the ventral process of the quadrate does not reach the vertical through the posterior margin of the symplectic and these features differentiate C. mojicai from Chrysobrycon myersi and C. yoliae (v. posterior margin of ventral process of quadrate reaching vertical through posterior margin of symplectic). In species of Chrysobrycon, the frontals are extensively contacting each other along the midline, resulting in an absent frontal fontanel and a reduced parietal fontanel. This extensive contact between the frontals modifying the fontanels is a condition rarely found within the Stevardiinae and hence is proposed as an additional diagnostic characteristic for the genus. An updated identification key for all Chrysobrycon species is provided.  相似文献   

20.
A remarkable Aulacus Jurine, 1807, A. ceciliae Turrisi, sp. nov., is described from Laos and A. bituberculatus Cameron, 1899 from India is redescribed from the type material, which has been recently rediscovered. For the latter species, a lectotype is formally designated. Both species are very characteristic due to the presence of two tooth‐like processes on the vertex, an autapomorphic feature probably related with the endoxylic bionomy. References to the other two Oriental species of Aulacus, A. philippinensis (Kieffer, 1916) and A. sinensis He & Chen, 2007 and a key to all four species of the genus presently known for the Oriental Region are provided.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号