新疆玛纳斯古近纪—新的鲤科鱼类

记述了新疆玛纳斯古近纪安集海河组发现的鲤科(Cyprinidae)一新属、种——刘氏天山鱼(Tianshanicus liui gen.et sp.nov.)。新属具有臀鳍分叉鳍条多于7根、体长形稍侧扁、口端位、下咽齿近锥形而齿尖前后略侧扁、背鳍和臀鳍均无硬棘、背鳍起点略在腹鳍起点之后以及尾鳍深分叉等特征,表明它应属于雅罗鱼亚科(Leuciscinae sensu Cavender & Coburn,1992)。然而,它又具有额骨前宽后窄、顶骨长方形、膜质蝶耳骨很大、齿骨冠状突较低、鳃盖骨近长方形等特征而有别于本亚科中其他属。值得注意的是,这些特征却见诸于现生的胭脂鱼类Myxocyprinus中,这将对研究雅罗鱼类的起源很有意义。根据鱼化石和哺乳化石的证据,认为含鱼层的时代为晚始新世。     

Historical biogeography of European leuciscins (Cyprinidae): evaluating the Lago Mare dispersal hypothesis

Aim To test the importance of the Lago Mare stage of the Messinian Salinity Crisis for the dispersal and diversification of European leuciscins (Cyprinidae: Leuciscinae). Location Europe. Methods Cytochrome b sequences of European leuciscins were employed to investigate phylogenetic relationships among species, using Bayesian inference, and to estimate times of diversification, using a relaxed molecular clock. The distributions of 190 European leuciscins were compiled, and regional species compositions were compared using a taxonomic similarity index and an area cladogram. Results Leuciscins restricted to the Iberian and Italian peninsulas and the West and South Balkan regions are phylogenetically more closely related to northern European species than to species from another southern European area. Application of a relaxed molecular clock to a Bayesian phylogeny indicates that most southern clades originated and diversified prior to the Messinian. Southern European regions are taxonomically distinct from one another, and from a more taxonomically homogeneous group of areas that includes Anatolia, East Balkans, Middle East, North Europe and West Russia. Main conclusions The scenario of a Messinian period of dispersal of Paratethyan fauna into Mediterranean regions, via the Lago Mare, predicts a rapid period of diversification and a pattern of close association among southern European faunas. Phylogenetic relationships among leuciscins, the timing of cladogenic events, and the taxonomic similarity among geographical regions do not conform to this expectation. The depth of clades endemic to southern Europe, together with the high levels of endemism in these regions, suggests that the faunas in these regions diverged prior to the Messinian and have evolved largely in isolation from one another. Our results support a model of gradual colonization of Mediterranean regions since the Oligocene. Subsequent connections between adjacent areas may have occurred in the Messinian or Pleistocene.     

A study of the systematics of cyprinid fishes by two-dimensional gel electrophoresis

This study was carried out to shed light on confused subfamilial groupings in the Cyprinidae from the biochemical viewpoint at the molecular level, specifically by using two-dimensional gel electrophoresis of liver proteins. Six pairs of cypriniform fishes, which are different from one another at familial, subfamilial, generic, specific, subspecific, and individual levels, were compared. The genetic distances between pairs of fishes increased as taxonomic ranks of the pairs became higher, confirming the reliable usefulness of this technique. Four species representing the different subfamilies, Cyprininae, Gobioninae, Acheilognathinae, and Leuciscinae, were compared to give new insight into relationships at the subfamilial level. Cyprinus carpio (Cyprininae) and Pseudogobio esocinus esocinus (Gobioninae) gave the smallest genetic distance and the largest values were obtained between either one of the above species and Acheilognathus melanogaster (Acheilognathinae), suggesting that the former two subfamilies compose the most closely related group that is in turn distantly related to Acheilognathinae. Tribolodon hakonensis (Leuciscinae) had almost equal genetic distances to the three other species.     

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.     

雅罗鱼亚科咽骨及咽齿的研究

本文根据对雅罗鱼亚科咽骨及咽齿的研究,将其咽骨分为三种类型。研究结果表明,本亚科咽骨形态及咽齿结构表现有与食性高度适应的现象。本亚科的咽齿有圆锥型,斜齿面型及特化型,这是对三种不同食性适应的结果。依据咽骨、咽齿的结构特点,试拟了雅罗鱼亚科属的检索。     

A new Pseudophoxinus (Teleostei,Cyprinidae) species from Asi River Drainage (Turkey)

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.     

Cephalic lateral line systems in the Far Eastern species of the genus Phoxinus (Cyprinidae)

The cephalic lateral line systems of seven Far Eastern Phoxinus species (P. phoxinus, P. kumgangensis, P. semotilus, P. lagowskii, P. oxycephalus, P. perenurus, and P. czekanowskii) were investigated. In this genus, the infraorbital canal is not connected with either the supraorbital canal or the preoperculomandibular canal. Phoxinus phoxinus is unique for having an underdeveloped condition, such as canal formation or remaining as uncovered. A unified supraorbital canal was observed in all species, but the infraorbital canal of both P. perenurus and P. czekanowskii was not unified into a single canal throughout their development. Unification between both sides of the supratemporal canal occurred in larger individuals of P. lagowskii, P. oxycephalus, and P. czekanowskii. The preoperculomandibular canal of P. kumgangensis, large P. lagowskii, and large P. oxycephalus was unified. The pore number of each part of the canal system also varied depending on the species. Intraspecific variations were observed between Korean and Japanese specimens of P. lagowskii in the unification of the supratemporal canal and the preoperculomandibular canal, and the number of pores of the supratemporal canal. It was inferred that the specific characteristic patterns of their cephalic lateral line systems reflected the following two factors: different environmental requirement for their microhabitat and different maximum body size.     

Detection, characterization and utility of a new highly variable nuclear marker region in several species of cyprinid fishes (Cyprinidae)

A new non-coding nuclear marker region was detected in two species of cyprinid fishes. Polymerase chain reaction primers were designed to amplify a part of this region in several genera, indicating a wide applicability within Cyprinidae. Sequence analysis revealed large intergeneric length variation caused by various deletion or insertion events. Apart from length variability, nucleotide differences were used for phylogenetic reconstructions, resulting in stable clustering of generic groups. We conclude that this nuclear region Cyfun P could be useful for the detection of intergeneric hybridization among members of the cyprinid family.