Diagnostic characters of two rare zoarcids, Krusensterniella multispinosa and K. pavlovskii (Pisces: Zoarcidae), with new data for the Sea of Okhotsk

Abstract

Diagnostic characters and taxonomic descriptions of two rare zoarcid fishes, Krusensterniella multispinosa Soldatov, 1922 and K. pavlovskii Andriashev, 1955 (family Zoarcidae), have been updated using the type and additional specimens. The type locality of K. multispinosa is located in the northwestern part of the Sea of Okhotsk (55°57ʹN, 138°13ʹE, depth 87 m). The lectotype (ZIN No 19961) was designated by P.Yu. Schmidt (1950). The morphological variability of the species is described, diagnosis is expanded. Additional differences from the species of related genus Gymnelopsis are specified. The distribution of K. multispinosa is limited to the Sea of Okhotsk and depths of 78–160 m. Krusensterniella pavlovskii was known by three type specimens from the Cape Africa, eastern Kamchatka (holotype ZIN No 33748, paratypes ZIN No 56576). Additional specimen derives from the north-eastern part of the Sea of Okhotsk (58°50ʹN, 157°02ʹE), which extends the known range of the species. The description of K. pavlovskii was updated, the diagnosis supplemented. Krusensterniella multispinosa and K. pavlovskii (subgenus Schantarella Andriashev, 1938) differ from other congeners in a larger number of pungent spines in the middle section of the dorsal fin D (XV–XXVI vs. I-XI). The both have 100–112 vertebrae, 95–110 dorsal-fin rays, and 81–94 anal-fin rays. In Krusensterniella pavlovskii unlike K. multispinosa, there are XXIII–XXVI pungent spines D (vs. XV–XX), 71–74 spiny rays in the anterior and middle parts of the dorsal fin (vs. 60–69), and 7 preoperculomandibular pores (vs. 6); the middle section of D with pungent spines is 83-112% of the length of the posterior section of D (43–72% in K. multispinosa) and 26–31% of the tail length, measured from the anal-fin origin to the caudal-fi n en d (vs. 17–22%); the scale cover reaching forward to the pectoral fins (in K. multispinosa not reaching the anal-fin origin.

A new fish of the genus Krusensterniella (Zoarcoidei: Zoarcidae) from the Kuril Islands

“…The methods used earlier for the study of Krusensterniella were applied (Chernova 2020(Chernova , 2022. D, A, P and C are the dorsal, anal, pectoral and caudal fins.…”

“…In the course of a latest revision, two multi-spine species, K. multispinosa Soldatov, 1922 andK. pavlovskii Andriashev, 1955 (with the number of pungent spines D XV-XX and XXIII-XXVI, respectively) were redescribed (Chernova 2020). Also, in the few-spine Krusensterniella group, three new species have been described (Chernova 2022).…”