Mitochondrial genomics of ostariophysan fishes: perspectives on phylogeny and biogeography

Abstract Ostariophysi is the second largest superorder within Teleostei. It contains five orders: Gonorynchiformes, Cypriniformes, Characiformes, Siluriformes, and Gymnotiformes. Resolving the higher-level relationships among ostariophysan and related fishes will aid in resolving basal teleostean divergence and provide basis to historical biogeographic analysis of major freshwater fish groups. In this study, we report the complete mitochondrial (mt) DNA sequences for eleven ostariophysan fishes and the results of phylogenetic analyses including these species plus four other ostariophysan and nine non-ostariophysan teleostean fishes. Maximum likelihood and maximum parsimony analyses reconfirmed clupeiforms as the closest relatives of ostariophysans. However, gonorynchiforms were closer to clupeiforms than to otophysans (ostariophysan groups excluding gonorynchiforms), thus raising a question over the current definition of Ostariophysi. The lack of clarity in otocephalan (ostariophysans + clupeiforms) basal relationships implies that such divergence took place over a short period of time. The monophyly of cypriniforms, characiphysans (characiforms, siluriforms, and gymnotiforms), and orders or superorders outside the ostariophysans examined here were conceivably reconstructed. The phylogenetic hypothesis suggests a Pangean origin of otophysans. Within characiphysans, gymnotiforms and siluriforms have independent evolutionary origins and evolutionary histories comparable to or older than that of characiforms. This helps to explain the present geographic distribution of characiphysans.     

A new genus of Nanaloricidae (Loricifera) from deep-sea sediments of volcanic origin in the Kilinailau Trench north of Papua New Guinea

A new genus and species of Nanaloricidae (Loricifera), Phoeniciloricus simplidigitatus, is described inhabiting fine sand covered by a layer of volcanic ash at a water depth of 1,813 m in the New Ireland Basin near the Kilinailau Trench (north of Papua New Guinea). The described specimen is a postlarva enclosed in a larval exuvium. This is the first report of a species belonging to the Nanaloricidae from the deep sea. This occurrence is surprising, because Nanaloricidae are typical inhabitants of coarse sands in the intertidal or littoral zone. Preference for these shallow water habitats is reflected in many morphological features which characterize the Nanaloricidae, and are not normally found in Loricifera inhabiting fine-grained, clayish, deep-sea bottoms. The postlarva of the new species is characterized by a long narrow mouth tube, an urn-shaped lorica divided into ten plates, and 13 small lorica spikes. Distinguishing features of the Higgins-larva include short spinose toes lacking mucros but having small and slightly enlarged bases, short scalids on the introvert, many thoracic plates arranged in 6–8 rows, numerous small papillate flosculi in the collar and caudal regions, and three pairs of filiform, short locomotory appendages on the ventral side. Some features of the new species, especially of the Higgins-larva, are discussed as adaptations to the deep-sea environment.Communicated by R.M. Kristensen     

Galaziella baikalensis, a new genus and species of chirocephalid (Crustacea: Branchiopoda: Anostraca) from Russia and the zoogeography of East Asian Anostraca

Galaziella baikalensis gen. et sp. nov. is described from Olkhon Island, Lake Baikal, Russia. The genus is assigned to the family Chirocephalidae Daday, 1910, on the basis of the following features: the male has two-segmented antenna, its basal segment bearing two leaf-shaped antennal appendages, all thoracopods with two distinctly divided pre-epipodites, and genital segments containing two clearly defined seminal vesicles. Galaziella is well distinguished from other genera of the family by the apical part of the penes, armed with "two spiniform processes" at each apex, instead of a single spine or toothed plate. Such male genital processes have not yet been found in Chirocephalidae, so that the diagnosis of the family is revised and two sub-families are proposed herein. Up to the present, 10 species belonging to 7 genera, including Galaziella baikalensis, and 5 families of Anostraca – Artemiidae, Branchinectidae, Branchipodidae, Chirocephalidae, and Thamnocephalidae – have been found in East Asia and its adjacent areas, including the Russian Far East, Mongolia, China, Korea, and Japan. The list includes all synonymic taxa. A distribution map and a key to the East Asian species of the family Chirocephalidae are provided. Received: November 22, 1999 / Accepted: May 2, 2000     

Rocky intertidal fish communities of California: temporal and spatial variation

Synopsis We examined data from our own and published collections of intertidal and shallow littoral fishes of the North American Pacific Coast with respect to temporal and spatial trends in species composition and dominance. We compared (1) recent and past intertidal collections made five and seven years apart, respectively, for two California localities, (2) intertidal collections from twelve localities in California, Oregon, and British Columbia, and (3) intertidal versus subtidal collections at one California locality. Temporal comparisons indicated substantially lower abundance of the cottid Oligocottus snyderi at two California localities during 1984, at one locality due to depressed abundance of young. Interannual differences in abundances suggested that other tidepool fish assemblages undergo significant changes as well. Geographical comparisons indicated general similarity in species composition, with cottids predominating in tidepools although several other families also were well represented (e.g., Stichaeidae, Scorpaenidae). Eel-shaped stichaeids and pholids occurred at high densities in exposed boulder fields. Both the tidepool and boulder field assemblages showed north-south changes in species abundances. Comparison of collections from the intertidal and subtidal zones at one California locality demonstrated that fishes of these habitats form two essentially distinct assemblages, with most species restricted to or concentrated in one or the other habitat.     

On the habitat and isolation of Gymnocharacinus bergi (Osteichthyes: Characidae)

Synopsis Gymnocharacinus bergi is a rare Paranensean fish which is the only characiform almost lacking scales in the adult. It is endemic and the only species in a peculiar spot — a tributary of the Valcheta creek — in the Somuncurá plateau in northern Patagonia, Argentina, over 300 km from the nearest place with a paranensean fish fauna. Besides its geographical isolation, G. bergi occurs within an area with climatic features drastically different from those currently associated with fishes from Neotropical temperate zones. We tested the assumption that water temperature in the naked characin habitat do not agree with the northern Patagonia climate. We also considered the isolation of G. bergi within the framework of an increasing inpoverishment of the paranensean ichthyofauna along a NE-SW axis in the Buenos Aires province. For this we applied a decrement equation used in island biogeography. Our findings demonstrate that the existence of G. bergi in its isolated habitat is possible because of the thermal traits of the water at the sources of the creeks, its temperature being independent of the climate of the area. The chemical composition of water was found to be within the range of common environments in the Buenos Aires pampas inhabited by several species of Paranensean fishes. Geographically, G. bergi lives in the last of a series of habitats which show a decreasing number of species correlated with the increasing distance from the La Plata River. Conservation status of the species is briefly discussed.     

Southern African skate biodiversity and distribution

The skates (Family Rajidae) have 12 genera and possibly 28 species off southern Africa (southern Angola, Namibia, South Africa and Mozambique). The geographic and bathymetric distribution and the taxonomic composition of the southern African skate fauna are analysed and the distribution mapped. The southern African skate fauna is best known off the temperate west coast of South Africa from the intertidal to approximately 1,200 meters, but poorly known below 1,200 m and sketchily known in warm-temperate and tropical parts of the area. Southern African skates of the temperate continental shelves above 100 m are not diverse and regularly include one species of the genus Dipturus, one species of Leucoraja, two species of Raja (including R. straeleni, the most abundant skate in southern African waters) and the giant skate Rostroraja alba. All of these skates are ‘shelf overlap’ species that range onto the outer shelves and uppermost slopes, and none are confined to inshore environments. Skate diversity increases on the outer shelves and upper slopes. At least half of the skate species are endemic to the southern African region; other species also occur off East or West Africa, a few extend to European waters, and records of one species, Amblyraja taaf, appear to be of strays from nearby sub-Antarctic seas. The genus Bathyraja and softnose skate group (Arhynchobatinae) are surprisingly limited (a single species) in deep-water off southern Africa (unlike other regions including the Antarctic), and almost all of southern African skates are members of the Rajinae. Amongst rajines, the tribes Amblyrajini (Amblyraja, two species, Leucoraja, two species, and Rajella, five species) Rajini (Dipturus, six species, Okamejei, one species, Raja, two species, and Rostroraja, one species), and Anacanthobatini (Anacanthobatis, two species, and Cruriraja, three species) predominate, while Gurgesiellini has a species of Neoraja and possibly two of Malacoraja.     

中国翼手目区系的研究及与日本翼手目区系的比较

翼手类是哺乳动物中唯一能够占领空间领域,真正飞行的一目。在现生哺乳纲中,为其种数仅次于啮齿类的一个大目,这无论就全世界来说,或者就中国来说,都是如此。以往中国对翼手目的报道,均散见于各区系报告中,缺乏专门系统研究,这同此类群之繁多是很不相称的,本文仅在材料很不充分的情况下,作初步概括性讨论。     

鲤科鲌亚科鱼类的系统发育及动物地理学

以雅罗鱼亚科为外群,采用分支系统学的原理和方法对鲌亚科17个属(须鳊属除外)进行了系统发育和动物地理学的分析.结果表明,(1)鲌亚科这17个属为一个单系群,并由4个较小的单系群组成;(2)鲌亚科现在的地理分布格局除源自离散事件外,主要源于扩散事件.鲌亚科的特征演化还表明,东亚地区地质历史的反转演化和平行演化可能在鲌亚科系统发育过程中起了重要的作用.     

云南兽类鼠科一新纪录——南洋鼠

正中国科学院昆明动物研究所哺乳动物生态与进化学科组于2014年9月20日在云南省西双版纳傣族自治州景洪市勐龙镇勐宋村(北纬21°30'00″,东经100°29'24″,海拔1 604 m)附近的常绿阔叶林中使用sherman捕获两号疑似费氏树鼠属标本。通过形态学鉴定结合分子遗传比较,确定这两号标本为南洋鼠(Chiromyscus langbianis)。     

湖北省兽类新纪录-台湾灰麝鼩

<正>台湾灰麝鼩(Crocidura tanakae Kuroda,1938)属于鼩形目(Soricomorpha)鼩鼱科(Soricidae)麝鼩属,在台湾地区分布较广(Fang et al.,1997),其模式标本产于台湾台中市南投县。其后,Ellerman和Morrison-Scott (1951)等认为其是灰麝鼩(Crocidura attenuata)的亚种或同物异名(Ellerman