卷 57, 编号 2 (2017)

A new species, Melanostigma olgae sp. n., is described from the Southern Ocean. The type series was obtained along the South Sandwich Islands (Scotia Sea, Western Antarctic) at the depths of 800−850 m. The new species differs from the other representatives of Melanostigma genus by the original combination of the features of the seismosensory system, axial skeleton, and coloration. The homologization of the structural elements (senses) of the head canals of the lateral line has been done for the first time for the Melanostigma. Morphology of M. olgae allows considering this species as the most evolutionary advanced within the representatives of this genus inhabiting the Southern Ocean. The key of the Antarctic species of the genus Melanostigma is provided.

The final part of the work provides the completion of the annotated taxonomic list of fish species found in freshwater and coastal brackish waters of Sakhalin Island, which includes 46 species belonging to 25 genera, nine families (Pholidae, Trichodontidae, Ammodytidae, Odontobutidae, Gobiidae, Paralichthyidae, Pleuronectidae, Monacanthidae, Tetraodontidae), and three orders (Perciformes, Pleuronectiformes, Tetraodontiformes). The comments on the ichthyofauna of fresh and brackish waters of Sakhalin are provided.

Biological features of the seven abundant commercial species—the Pacific halibut Hippoglossus stenolepis, the Greenland halibut Reinhardtius hippoglossoides, the Alaska plaice Pleuronectes quadrituberculatus, the northern rock sole Lepidopsetta polyxystra, the yellowfin sole Limanda aspera, the flathead sole Hippoglossoides elassodon, and the Bering flounder H. robustus (Pleuronectidae)—have been studied for a 20-year period (1995−2015). These species are present in the northwestern Bering Sea in the summer–autumn season; they form the gatherings in Olyutorsky-Navarin region. The size-weight spectra of the fish caught by different fishing gear has been analyzed, the peculiarities of the linear growth and the weight gain, as well as the spawning period and scale and the spawning conditions, have been described. The largest halibut specimens have been registered in the bottom setlines and gill nets, while flounders were in snurrevad catches; the smallest specimens have been observed in trawl catches. The abundant year-class in most of the studied species is seen well on the long-term plots of the fish size spectra and is tracked by the decrease of their biological parameters. The species that demand vast growing grounds (Pacific halibut, Alaska plaice, northern rock sole, and yellowfin sole) are characterized by a smaller average body size of the fish sampled in the coastal waters due to the prevalence of the young specimens in this area.

Anadromous and stream resident Dolly Varden S. malma were compared in the contaminated and reference rivers across Kamchatka region. Anadromous Dolly Varden’s fry from the polluted and clean rivers were correspondently different by reduced growth rate and narrow length variability. It was observed that juveniles prefer to migrate from the polluted river sections; only seldom fry reaches the smoltification stage at the contaminated sites. The volcanogenic environmental pollution causes paedomorphosis and accelerated sexual maturation in the landlocked brook-dwelling populations. Either the growth rate or the length variability within the age groups were not reduced during the maturation period in the landlocked groups comparing with fish from reference streams. However the weakened individuals with an extremely low body weight were observed among the landlocked fish during maturing. Gonadosomatic index and relative fecundity were comparable for fish from polluted and clean rivers, though relatively high fecundity for the first group was attained by the oocytes size decreasing. Skin cover was damaged; Clark’s condition index and muscle fatness were reduced while liver size was enlarged in either landlocked or anadromous fishes from the polluted water-courses.

The article reports DNA barcoding (sequencing of the cox 1 mitochondrial gene fragment) of five South Atlantic flying fish species belonging to family Exocoetidae together with the results of the comparative analysis of cox 1 variability in the Exocoetidae and its closely related family Hemiramphidae. It has been demonstrated that DNA barcoding can be used as an extra tool for species identification and phylogenetic analysis in flying fish, since species identification accuracy using the cox 1 gene sequence proved to be 88%, or 78% when intraspecies variability level is taken into account. We have confirmed monophyletic origin of certain species, genera, and subfamilies of flying fish except for the genus Cheilopogon, which was represented on the phylogenetic tree by three paraphyletic clades. One of them shows close relationship to the genus Cypselurus, while another encompasses Hirundichthys genus species. The Exocoetidae is characterized by much lower overall genetic divergence level compared to the Hemiramphidae (average intraspecies differences: 10.2 ± 0.4% vs. 18.1 ± 0.8%; average intrageneric differences: 13.3 ± 1.1% vs. 21.3 ± 1.8%), which may indicate that the former group is relatively young in terms of evolution. No intraspecies differentiation was observed for Exocoetus obtusirostrus across a significant geographic distance (>3000 km). Phylogenetic reconstructions based on the variability of conservative (cox 1 mtDNA) and more variable regions of mitochondrial and nuclear genomes and on the adaptive morphological traits associated with gliding flight development were shown to coincide to a large extent.

In common carp Cyprinus carpio, acclimated to NaCl content in water of 0–6 g/L, the concentration of sodium in blood plasma was relatively constant (130.8 ± 0.7 mM/L). In the fish acclimated to 6−12 g/L NaCl, which corresponds to critical water salinity, plasma sodium content rose to the maximal value of 205.6 ± 1.3 mM/L. Within the interval of water salinity of 0–6 g/L NaCl, the content of potassium in erythrocytes exhibits a trend to gradual decrease from 104.8 ± 1.6 mM/L to 96 ± 1.5 mM/L. In the zone of critical salinity, potassium content increases exponentially to 130.3 ± 2.9 mM/L. The erythrocytes adapted to the increase in osmotic concentration of plasma by accumulation of potassium ions. According to published data on the studies in vitro, the erythrocytes adapt to hypertonic solutions by means of increase in intracellular sodium concentration. Possible reasons for discrepancy between the results of in vivo and in vitro studies are discussed in the present paper.

A new species, Tryssogobius fisunovi sp. n., is described from the depth of 73 m in the region of the Anambas Islands (Indonesia), South China Sea. Based on the presence of the preopercular and orbito-scapular canals, the species is similar to T. porosus, but it differs from the latter species in coloration, location of the mental row of genipores f, separated pelvic fins, and other characters. The problems of the systematics of the genera Tryssogobius and Obliquogobius are discussed.

The first record of the rare deep-sea goblin shark, Mitsukurina owstoni, was reported from the waters of Morocco (Northwest Africa). Occurrences of this species have been recorded earlier from the waters of Madeira (over 1000 km to the north) and Senegal (over 800 km to the south of the place of our record).

One specimen (300 mm in standard length) of Saloptia powelli, belonging to the family Serranidae, was newly collected in a local fish market in Manado, North Sulawesi, constituting a new record for the species in the Indonesian archipelago. This species was diagnosed by the following morphological traits: dorsal rays VIII—11, anal rays III—8, well-defined opercular spines, pelvic fins below pectoral fins, caudal fin emarginate, mouth moderate in size, supplemental maxillary present, fine teeth in irregular rows on vomer and palatines. Head, body, and fins yellow in color. We suggest “kerapu emas”, a translation of its existing common name “golden grouper”, for the Indonesian species names.