M. V. Nazarkin

Zoarces fedorovi sp. nova (Perciformes: Zoarcidae)—A new species of eelpout from the Taui Bay of the Sea of Okhotsk

The description of a new species of the genus Zoarces, Z. fedorovi, widespread in the Taui Bay of the Sea of Okhotsk in freshened sites of coastal waters and near-mouth sections of rivers is provided. The new species inhabits sympatrically with the eastern eelpout Z. elongatus; however, it differs from the latter and other Pacific species of eelpouts (Z. gillii and Z. andriashevi) by a considerably smaller number of rays in unpaired and pectoral fins, head and trunk proportions, some specific features of coloration, and the mode of life. Z. fedorovi is similar to the last two species in the presence of one (more seldom, two–three) black rounded spot at the beginning of the dorsal fin; however, like Z. elongatus, it is characterized by the absence of a direct contact between the inner edges of parietal bones separated by the upper-occipital bone. A key to identification of species of the genus Zoarces is presented.

Redescription of Andriashev’s spiny pimpled lumpsucker Eumicrotremus andriashevi and designation of a new subspecies E. andriashevi aculeatus ssp. n. (Cyclopteridae)

The redescription of Eumicrotremus andriashevi Perminov, 1936, and designation of the new subspecies Eumicrotremus andriashevi aculeatus Voskoboinikova et Nazarkin ssp. n. (Litke Strait, Bering Sea) have been performed. E. andriashevi aculeatus differs from the nominative subspecies by the presence of larger and higher bone plaques that form the “cheeks” and make the external view of the fish “disheveled” and by the larger body height and smaller snout length, as well as by the shape of the infraorbitals and mesethmoideum.

Comparative Osteology, Relationships, and Systematics of Fish of the Genus Zoarces (Zoarcidae, Perciformes)

Comparative-osteological investigation of all species of the genus Zoarces is made: Z. fedorovi, Z. andriashevi, Z. elongatus, Z. viviparus, Z. americanus, and Z. gillii. In the skeleton of hyoid arch in species of Zoarces, Lycozoarces, and Lycodes, paired bony elements are found, not described previously, identified as parurohyalia which may be synapomorphy of Zoarcidae. Differences between the Zoarces species are revealed by 56 external morphological and osteological characters. Cladistic analysis yielded one tree 135, Ci 0.57, Ri 0.54 long. Cladistic analysis confirms validity of a recently described species Z. fedorovi, which turned out to be the most generalized in the genus Zoarces, as well as the validity of Z. elongatus. The species Z. americanus and Z. gillii occupy a terminal position preventing their isolation to independent genera as was previously supposed, as this would lead to paraphyly of the genus Zoarces.

Comparative morphological analysis of big-scaled redfin Tribolodon hakonensis Günther, 1877 (Cyprinidae, Cypriniformes) from Sakhalin and southern Primorye

Comparative analysis of plastic and meristic characteristics of big-scaled redfin Tribolodon hakonensis from Sakhalin and southern Primorye has been performed. The considerable differences revealed are supported by results of genetic studies. The results of comparison of morphology of big-scaled and Pacific T. brandtii redfins with the purpose of assessing the probability of the previously advanced hypothesis on the origin of the “southern” form of big-scaled redfin are provided.

Georgimarinus gen. nov.—A new genus of the family Cyclopteridae (Cottoidei)

New genus of cyclopterids, Georgimarinus gen. nov., is established for Eumicrotremus barbatus (Lindberg et Legeza, 1955). The new genus is characterized by the next unique apomorphies: teeth in the outer row at symphysis of premaxillae fuse with premaxillae, teeth at symphysis of dentary fuse among themselves and with dentary, forming the regular cutting edge; there are numerous barbs on the head and body; the bony plaques located in centers of connective tissue tubercles leaving the edges free.

Morphology of two eastern Pacific eelpouts (Pisces, Zoarcidae, Lycodes) in connection with features of distribution of species with a double lateral line

Morphology of two endemic eastern Pacific species of eelpouts—blackbelly Lycodes pacificus Collett, 1879 and bigfin L. cortezianus Gilbert, 1891—were studied. It was shown that these two species are characterized by unreduced seismosensory system of the head and belong to a species group with a double lateral line. It was suggested that the ancestral form of this species group could have possibly dispersed in the Atlantic Ocean through the Panama Canal in the pre-Pleistocene time. It is likely that the antitropical distribution of the Newfoundland eelpout L. terranovae is related this event.

On the Identity of Two Species of Eelpouts (Pisces: Zoarcidae) from the Sea of Okhotsk

Morphology of two similar species of eelpouts—Lycodes microlepidotusSchmidt, 1950 and L. ochotensisSchmidt, 1950—is investigated. It is shown that L. ochotensisis a junior synonym of L. microlepidotus.Morphological description of this species is presented based on 30 specimens known at present

New Findings and Redescription of Holotype of Eelpout Lycodes semenovi Popov, 1931 (Perciformes: Zoarcidae)

New findings of representatives of the endemic Sea of Okhotsk species—eelpout Lycodes semenovi Popov, 1931 (Perciformes: Zoarcidae)—previously known only from the type specimen are reported. The morphological description of available individuals of this rare species is provided.

Redescription of large-scale eelpout Lycodes macrolepis Taranetz et Andriashev, 1935 (Perciformes: Zoarcidae)

Morphology of a rare species—large-scale eelpout Lycodes macrolepis Taranetz et Andriashev, 1935—has been studied. It was shown that the main lateral line of this species has a ventrolateral configuration rather than medial, as was considered previously. Large-scale eelpout is an endemic species of the Sea of Okhotsk; evidence of its finding in the Sea of Japan is based on the erroneous classification of another eelpout species.

Comparative Osteology of Cyclopsis tentacularis (Cyclopteridae, Scorpaeniformes)

The structure of the skeleton of Cyclopsis tentacularis, an endemic species from the northern part of the Sea of Okhotsk, is studied for the first time. Generally, it corresponds to that in other representatives of Cyclopteridae. The differences in structure of Cyclopsis and of other investigated cyclopterids are both plesiomorphic and apomorphic. The plesiomorphic ones are comprised of sutural articulation of pteroticum and prooticum, spiny ray in the beginning of D2, berycoid opening in ceratohyale, bony pharyngobranchiale 2, emergination in the anterior margin of scapula, and postcoracoid opening in coracoideum. The apomorphic ones are separation of parietalia, absence of bony basibranchialia, presence of emargination in the posterior margin of supracleithrum, and reduction of several last epipleural ribs. The presence of numerous plesiomorphies does not confirm Ueno’s viewpoint (Ueno, 1970) on the advanced position of Cyclopsis in the family Cyclopteridae. Final conclusions on the position of Cycloposis in the system of cyclopteridae and of the system of this family itself may be made only after proper investigation of the external morphology and osteology of all genera of Cyclopteridae.