卷 56, 编号 5 (2016)

The anatomic and morphological description is given to the scaled thornfish Bovichtus psychrolutes, based on the materials from the known areas (New Zealand Plateau) and new parts of the geographic range (eastern margin of the New Zealand Basin: Ridge of Hercules and Pulkovo Ridge, Eltanin-Heezen Fault System). The type specimens of several species of Bovichtus from the collections in London and Wellington museums have been revised. B. oculus is synonymized with B. psychrolutes. The geographic range of B. psychrolutes covers the Pacific sector of notal waters and partly Antarctic waters of the Southern Ocean in the circumglobal ring of the forms of the species of Bovichtus; its range lies between the ranges of B. variegatus (southern New Zealand down to Auckland Islands, New Zealand Plateau) and B. chilensis (southern South America down to Antarctic Peninsula).

In connection with the problems of identification of certain species of the genus Ponticola, and especially their juveniles, morphological and genetic studies of gobies collected in the northwestern part of the Black Sea basin were carried out using literature data and museum collections. Karyological data indicate a distinct species status of western (P. odessicus) and eastern (P. eurycephalus) mushroom gobies; the range of the latter includes not only the Sea of Azov but also waters of the Black Sea coast of the Crimean Peninsula; these conclusions are supported by preliminary molecular genetic studies. Based on the obtained results of intraspecific morphological variability of species, we propose morphological characteristics for identification of adult P. syrman and P. odessicus, as well as a specific set of characteristics to identify juvenile (body length less than 50 mm) P. syrman, P. kessleri, and P. odessicus. We reveal differences in the karyotype structure of P. syrman from populations of the Sasyk Lake and the Don River, which do not differ in terms of external morphological characteristics and variability of cytochrome b haplotypes. The need for further research of phylogeography and morphological and karyological variability of P. syrman sensu lato is assumed.

The hydrothermal vent in Frolikha Bay and the methane cold seep “Saint Petersburg” in Baikal Lake are characterized by the highly productive communities of the aquatic invertebrates and cottoid fish (Cottoidei). The benthic and pelagic ichthyofauna of the vent comprises twelve key species belonging to eight genera, while that of the seep comprise eight species (six genera belonging to three families). The only one obligate hydrothermal species, N. thermalis, has been found; it dominated by abundance (91.6% of total abundance) in Frolikha Bay. N. werestschagini dominated in the cold seep community (39.5%). The spatial distribution of the fish around the hydrothermal vents and the cold seeps was patchy. The largest schoolings has been observed in two biotopes, in the areas of the silty bottom sediments and at the areas covered by the bacterial mats, as well as in the near-bottom water layer.

Historical data for the period 1929−2011 were used to generalize information on the seasonal feeding migrations of Pacific sardine to the shores of Sakhalin Island. In the 20th century, the cyclicity of sardine occurrence in the Tatar Strait and southwestern part of the Sea of Okhotsk appeared to have a similar character. Sardine distribution patterns are considered in connection with the oceanological characteristics on these areas. A close correlated relationship was revealed between the SST anomalies and northern boundary of distribution of this subtropical fish. Besides the water temperature, Pacific sardine northern migrations have been formed under the influence of many other factors (by origin and impact), including fluctuations in abundance, index of stock biomass, food supply, state of marine ecosystems, and climatic conditions.

Pink salmon introduced into the White Sea started to exploit as spawning grounds middle and upper reaches of the river 20 years after its appearance in the Indera River. As a result of this, the migration pathway of smolts and late smolts appeared in addition to early smolts. The intraspecies polymorphism of smolts is confirmed by differences of early and late smolts by body length and weight, migration dates, food spectrum, and indices of stomach fullness. The food spectra of late juveniles of pink salmon coincide with those of parr of Atlantic salmon Salmo salar and of brown trout S. trutta. Greater abundance of late migrants of pink salmon may cause competition of these species for food.

The histological study of the adult specimens of walleye pollock Theragra chalcogramma carrying filamentous gonads evidenced that this group comprised males, females, and sterile fish. The specimens carrying the filamentous gonads have been found mostly in the elder age groups; no maturing of the oocytes or sperm cells has been registered. The frequency of occurrence of such specimens was relatively low: 0.07–0.13% in the Sea of Okhotsk and up to 0.25% in the Bering Sea. We conclude that these specimens have nearly no effect on the reproductive success of this species.

The size and age composition of the population of Black and Caspian Sea sprat Clupeonella cultriventris, as well as the variation of the growth of fish in the reservoirs of the upper reaches of the Volga, are reported and a comparative analysis of group and individual variability of fish growth within the native (Caspian, Azov, and Black seas) and contemporary (formed due to invasion) ranges is presented. The degree of variability and the asymmetry of sprat body length distribution have been shown to increase under the conditions of large population sizes, deficit of food, and slow growth. Variability was also elevated near the borders of the range of the species, notwithstanding the abundance of food. It is shown that invasion of sea walnut comb jelly Mnemiopsis leydi into the Azov and Caspian Seas had so undermined feed base of sprat, that it is not only decreased its abundance and fecundity but also slowed growth of the fish.

A new species, Gobiopsis uranophilus sp. n., is described off the Anambas Islands, South China Sea, from a depth of 73 m. The species is similar to the deepwater Japanese species G. namnas, but it differs in the dorsal orientation of the eyes, total absence of pores of the seismosensory system on the head, number of fin rays, and other characters. The similar patterns of the two species (presence of scales on the sides of the head, absence of the barbel-shaped appendages on the head, and large scales on the body), most likely, are connected with their adaptation to deepwater habitats.