Some preliminary results of research on Emperor Seamounts in April, 2019

“Firefly” of the Submarine Mountains: New Data on Physiculus cynodon (Moridae, Teleostei) from Emperor Seamounts and Northwestern Hawaiian Ridge

“…All specimens had canine teeth on the jaws (Figure 1), about 180 scales in the lateral line, and 59-61 vertebrae (calculations were made from radiographs). These key external morphological characters correspond well to the description of P. cynodon presented by Sazonov [20], Okamoto et al [7], and Prokofiev [22]. All records from the TINRO database related to P. japonicus from the waters around the Emperor Seamounts and northwestern Hawaiian Ridge were referred by us to P. cynodon based on the following considerations: P. japonicus is not found in this area since its range is limited to the waters of the southern Sea of Japan, the Pacific coast of Japan, the East China Sea, and the seamounts east of the Japanese Archipelago [11][12][13][14][15].…”

“…Species identification was conducted via examination of five specimens caught in 2019 on the Koko Seamount [20] and deposited in the fish collection of the Shirshov Institute of Oceanology, Russian Academy of Sciences (IO RAS, uncatalogued). All specimens had canine teeth on the jaws (Figure 1), about 180 scales in the lateral line, and 59-61 vertebrae (calculations were made from radiographs).…”

“…Borets [9] reported (as P. japonicus) that P. cynodon is found throughout the study area from Lira Seamount in the northwest to Academician Berg Seamount in the southeast. There are no confirmed records of this species in northernmost locations in published literature [20,57,58]. Physiculus cynodon has never been a targeted species on the seamounts under study.…”

“…Data on the abundance of P. cynodon within its range are limited. Published literature provides population densities for Koko Seamount in 2010 [19] and 2019 [20]. The minimum recorded catch in 1982 on Koko Seamount averaged 0.9 kg/km 2 .…”

Morphology and phylogeny of the parasitic nematode Mooleptus rabuka (Machida, Ogawa & Okiyama, 1982) (Rhabditida, Spirurina: Mooleptinae nom. nov.), with notes on taxonomy of the family Gnathostomatidae

“…A specimen of A . fedorovi was caught from the R/V Professor Kaganovsky on April 12, 2019, during a deep-water trawl survey (Somov et al ., 2019) in the area of the Imperial Ridge (Ojin Seamount, Pacific Ocean) at a depth of 1025 meters (37°57′06″N, 170°24′07″E). Four worms, one male and three females, were collected from the shark's stomach.…”