中国浙江缨口鳅属一新种(鲤形目,平鳍鳅科,腹吸鳅亚科)

1983年8月作者在浙江泰顺县乌岩岭国家自然保护区采集到缨口鳅属鱼类25尾,经鉴定为1新种.新种吻褶发达,吻须较长,最长吻须约为眼径的1.5倍;吻须排成1排,基部均与吻褶相连,与缨口鳅Crossostoma davidi Sauvage,1878相似,而明显区别于属内其它物种,但两者在以下性状上又存在明显区别:1)新种体侧具有18～22条横纹;2)腹部中央无鳞区延伸到胸鳍和腹鳍中点之后;3)分布区亦不同,新种仅分布于浙江飞云江水系,缨口鳅分布于福建闽江水系.     

云南东部云南鳅属二新种记述(鲤形目：鳅科)

描述采于云南东部南盘江水系的云南鳅属鱼类２新种,以其形态特征分别命名为大鳞云南鳅Ｙｕｎｎａｎｉｌｕｓ ｍａｃｒｏｌｅｐｉｓ Ｌｉ,Ｔａｏ ｅｔ Ｍａｏ,ｓｐ．ｎｏｖ．和长背云南鳅Ｙｕｎｎａｎｉｌｕｓ ｌｏｎｇｉｄｏｒｓａｌｉｓ Ｌｉ,Ｔａｏｅｔ Ｌｕ,ｓｐ．ｎｏｖ．。     

High level of gene silencing in the tetraploid goldfish

The goldfish, Carassius auratus, is a karyotypically tetraploid form that expresses only 19% of its enzyme-encoding loci in duplicate. This level of gene duplication is among the lowest reported among tetraploid cypriniform fishes and may be related to the intense selective and drift processes associated with its domestication.     

Triplophysa ferganaensis,a new loach species from Fergana Valley in Central Asia (Teleostei: Nemacheilidae)

Triplophysa ferganaensis sp. nov. is described from the Shakhimardan stream, a small tributary of the Syr Darya, which does not reach the river in Fergana Valley. It can be distinguished from other valid Triplophysa loaches based on the following combination of characters: body smooth and scaleless, lateral line complete, posterior chamber of air bladder degenerated, inner gill rakers 10–11 on the first-gill arch, outer gill rakers absent, vertebrae 4 + 35–36, 8 + 8 branched caudal-fin rays, caudal peduncle depth 2.1–2.7 times its length, two supratemporal pores, dorsal-fin origin closer to the caudal-fin base than to the snout tip, caudal fin emarginated and pelvic-fin tip reaching the anus. The new species can also be distinguished from its congeners based on the molecular analyses of mitochondrial cytochrome oxidase subunit I (coI) gene sequences. The phylogenetic position of this new species indicates that it is a sister taxon of Triplophysa tenuis.     

Morphological variation in the Weberian apparatus of Cypriniformes

Cypriniformes (which includes the minnows, carps, loaches, algae-eaters, stone loaches, and suckers) is a morphologically diverse and incredibly speciose order of teleosts. It has been suggested that a number of evolutionary innovations, key to improved hearing and feeding, have played an important role in cypriniform fishes' success. One such innovation, the Weberian apparatus, is a novel assemblage of vertebral elements and modified ribs that relay and amplify sound pressure changes from the gas bladder to the inner ear. The Weberian apparatus unites Cypriniformes with other major orders into an extremely species-rich group of fishes, the Otophysi. Together, otophysan fishes comprise one of the largest groups of fishes in the world, as well as the majority of freshwater fishes. Here we present a detailed comparison of the Weberian apparatus in a number of cypriniform families using cleared and stained specimens. We present data regarding inter- and intrafamilial morphological variation within Cypriniformes. With few, but evolutionarily important, exceptions we find that diagnostic features of the Weberian apparatus characterize each family. Interspecific variation within each of the families Balitoridae, Gyrinocheilidae, and Catostomidae is only slight, whereas variation among subfamilies within Cyprinidae and Cobitidae is far more significant. This comparative study identifies a number of distinct morphologies, some of which appear highly correlated with ecological niche. For example, inhabiting swift-moving waters appears to be a key factor in the encapsulation of the anterior gas bladder in some cobitids, balitorids, and gobionin cyprinids.     

云南石林洞穴金线鲃一新种(鲤形目,鲤科)

2006年4月12日和18日作者于云南省石林县石林镇落水洞(蝙蝠洞)地下伏流(属珠江水系)采集到金线鲃属鱼类标本9尾,经鉴定为1新种.新种被命名为宽角金线鲃Sinocyclocheilus broadihornes sp. nov.;以其头上长有一个骨质角状突和体表裸露,仅存侧线鳞等鉴别特征,与犀角金线鲃S.rhinocerous Li et Tao相近,而明显区别于属内的其余种.但新种头上骨质突起为1个等边三角形状的角与后者的犀角型角不同;新种吻端与两鼻孔间有3个突起,呈品字形分布,后者平滑.     

Phylogeography of Rhinichthys cataractae (Teleostei: Cyprinidae): pre‐glacial colonization across the Continental Divide and Pleistocene diversification within the Rio Grande drainage

The longnose dace, Rhinichthys cataractae, is a primary freshwater fish inhabiting riffle habitats in small headwater rivers and streams across the North American continent, including drainages east and west of the Continental Divide. The mitochondrially encoded cytochrome b gene (1140 bp) and 2298–2346 bp of the nuclear‐encoded genes S7 and RAG1 were obtained from 87 individuals of R. cataractae (collected from 17 sites throughout its range) and from several close relatives. Phylogenetic analyses recovered a monophyletic R. cataractae species‐group that contained Rhinichthys evermanni, Rhinichthys sp. ‘Millicoma dace’, and a non‐exclusive R. cataractae. Within the R. cataractae species‐group, two well‐supported lineages were identified, including a western lineage (containing R. evermanni, R. sp. ‘Millicoma dace’ and individuals of R. cataractae from Pacific slope drainages) and an eastern lineage (containing individuals of R. cataractae from Arctic, Atlantic, and Gulf slope drainages). Within the eastern lineage of R. cataractae, two well‐supported groups were recovered: a south‐eastern group, containing individuals from the Atlantic slope, southern tributaries to the Mississippi River, and the Rio Grande drainage; and a north‐eastern group, containing individuals from the Arctic slope and northern tributaries to the Mississippi River. Estimates of the timing of divergence within the R. cataractae species‐group, combined with ancestral area‐reconstruction methods, indicate a separation between the eastern and western lineages during the Pliocene to early‐Pleistocene, with a direction of colonization from the west of the Continental Divide eastward. Within the southern portion of its range, R. cataractae likely entered the Rio Grande drainage during the Pleistocene via stream capture events between the Arkansas River (Mississippi River drainage) and headwaters of the Rio Grande. A close relationship between populations of R. cataractae in the Rio Grande drainage and the adjacent Canadian River (Mississippi River drainage) is consistent with hypothesized stream capture events between the Pecos (Rio Grande drainage) and Canadian rivers during the late‐Pleistocene. The population of R. cataractae in the lower Rio Grande may have become separated from other populations in the Rio Grande drainage (upper Rio Grande and Pecos River) and Canadian River during the late‐Pleistocene, well before initiation of recent and significant anthropogenic disturbance within the Rio Grande drainage. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 317–333.     

Across the highest mountain on earth: discordant phylogeographic patterns and recent dispersal of Tibetan stone loaches (Triplophysa) in the Himalayas

Phylogeographic congruence among co-distributed taxa is regarded as an inherent inference to vicariance events. Nonetheless, incongruent patterns of contemporary lineage divergence among taxa indicated that species differ in their response to common past events. To investigate the role of past events, ecological traits and lineage diversification time in shaping the contemporary phylogeographic patterns, comparative analyses were conducted for Tibetan stone loaches in the Himalayas using three gene markers and two ecological traits (depth of caudal peduncle in their length and presence/absence of posterior chamber of the air bladder). By a thorough sampling in two flanks of the Himalayas, the authors detected that phylogenetic breaks were spatially discordant and divergences of populations were also temporally asynchronous in co-distributed loaches. Estimated divergence time using fossil-calibrated node dating indicated that the Tibetan stone loaches colonised into the south flank of the Himalayas until the Pleistocene. The demographic expansions were also disconcerted between populations in north and south flanks, or east and west Himalayas. Ongoing gene flows between populations in north and south sides implied that the Himalayas do not strictly impede dispersal of cold-adapted species. The results highlight that the quaternary climatic oscillation, in conjunction with ecological traits and lineage diversification time, shaped contemporary phylogenetic patterns of stone loaches in the Himalayas and provide new insights into the biodiversity and composition of species in the Himalayas and surrounding region.     

云南似原吸鳅属鱼类一新种记述(鲤形目,平鳍鳅科)

2003年6月2日作者于云南省沾益县德泽乡牛栏江(属金沙江水系)采集到似原吸鳅属鱼类7尾标本,经鉴定为1新种.新种鳃孔窄,可与同属中鳃孔较宽的似原吸鳅Paraprotomyzon multifasciatus和龙口似原吸鳅P.lungkowensis明显区分,而与鳃孔窄的巴马似原吸鳅P.bamaensis和云南似原吸鳅P.yunnanensis相似.新种与巴马似原吸鳅P.bamaensis相比,两者在下列特征上可明显区分:1)新种下唇无向后伸展的唇片,后者具唇片;2)新种吻褶两侧后角之后具侧沟,后具无侧沟;3)新种腹鳍为i-15～17,后者为i-12～13.与云南似原吸鳅P.yunnanensis相比,两者的鉴别特征如下:1)新种吻褶后侧具侧沟,后者吻褶后侧无侧沟;2)新种胸鳍为i-19～22,而后者为i-26;3)新种腹鳍为i-15～17,后者为i-20.     

Triplophysa rosa sp. nov.: a new blind loach from China

A new blind loach of Triplophysa Rendahl 1933 was collected from a subterranean pool in a cave at Wulong County, Chongqing City, China, in November 2002. The new species, named Triplophysa rosa sp. nov., can be distinguished from its congeners by the following unique characters: eyes vestigial; 9 branched dorsal‐fin rays; 12 branched pectoral‐fin rays; 7 branched pelvic‐fin rays; 6 branched anal‐fin rays; 7 + 7 branched caudal‐fin rays; distal margin of dorsal‐fin concave; tip of pelvic‐fin surpasses vertical level of anus; caudal‐fin deeply forked; whole body scaleless and colourless.