Epigonus merleni McCosker and Long, 1997 was originally described on the basis of a single specimen collected from the Galapagos Islands. It was considered to be distinguished from E. macrops (Brauer, 1906) by having 11+14 vertebrae and 57 lateral-line scales, but our examination of the holotype of E. merleni revealed that it actually has 10+15 vertebrae and 48+5 lateral-line scales. The holotype also has a luminescent window near the pelvic-fin base that is otherwise unique to E. macrops in the genus. Based on our comparison of the holotype of E. merleni with a syntype and other specimens of E. macrops, we conclude that E. merleni is a junior synonym of E. macrops.
Sixteen specimens of Ernogrammus zhirmunskii Markevich and Kharin, 2011, formerly known only from Peter the Great Bay, Russia, were collected from Volcano Bay on the Pacific coast of Hokkaido and from Shizugawa Bay, Miyagi Prefecture, Pacific coast of the northern Honshu, Japan. This species is redescribed on the basis of these specimens and several errors in the original description are corrected. This species is easily distinguished from other stichaeid fishes in having a diagnostic lateral-line pattern and a rigid spine in the posteriormost part of the anal fin.
A large series of Peristedion barbiger (Garman, 1899) was collected in the eastern Pacific off Peru during a joint survey conducted by the Japan Deep Sea Trawlers Association and the Instituto del Mar del Peru in 1998-2003. No detailed description of P. barbiger has been published since the original description, and the availability of 285 new specimens provided an opportunity to determine the extent morphological variability within this species. Our study revealed that the presence or absence of nasal spines and the shape of the preopercular margin, both having been used previously as taxonomic characters, vary intraspecifically. The species is diagnosed as having 16-19 dorsal-fin soft rays; 31-34 bony plates in the upper lateral row; 14-19 lower gill rakers; 17-25 chin barbels in total; short pectoral fin, 13.3-17.8% of SL; a relatively short pair of filamentous barbel on the lip, 26.4-57.1% of HL; a broad, spatulate rostral projection of a length 19.7-39.5% of HL; and a large black spot on the spinous portion of the dorsal fin. In addition, we herein designate a lectotype for P. barbiger.
A poorly known scorpionfish (Scorpaenidae), Phenacoscorpius eschmeyeri Parin and Mandrytsa, 1992, has been known only from the holotype from the Sala y Gomez Ridge, southeastern Pacific Ocean. Two new specimens of the species, collected from the Nazca Ridge, near the type locality, and found in the fish collection of the Hokkaido University Museum, are described in detail. The holotype was also reexamined. The two diagnostic characters of the species given in the original description to separate it from a related congener, Phenacoscorpius adenensis Norman, 1939, were found to be invalid, but a new series of diagnostic characters was found. A revised diagnosis of the species is thereupon provided. A color photograph of P. eschmeyeri when fresh is published for the first time.
A new scorpionfish, Phenacoscorpius longilineatus n. sp., is described on the basis of 94 specimens from New Caledonia and New Zealand in the southwestern Pacific Ocean, at depths of 345-1089m. The new species is distinguished from its congeners by the following combination of characters: 8-18 (mode 12) pored lateral-line scales, last of which is situated from below base of seventh spine to below base of fourth dorsal-fin soft ray; no slit behind fourth gill arch; palatine teeth present; second preopercular spine always absent; nuchal and parietal spines distinct; nape and anterior body strongly arched in adults of over ca. 80mm standard length (SL); post-nuchal-spine length 5.0-9.7% (mean 7.2%) of SL; caudal fin length 21.4-26.7% (mean 23.4%) of SL; 1-5 (mode 2) black spots on posterior half of caudal peduncle; and body usually uniformly whitish without distinct dark saddles in preserved specimens. In addition, P. adenensis Norman, 1939, which is similar to P. longilineatus morphologically, is redescribed on the basis of 3 specimens from the western Indian Ocean and 52 specimens from the southwestern Pacific. The latter represent the first records of this species outside the western Indian Ocean.
The morphology of the pectoral fin muscles of lizardfishes (Synodontidae) is described. Members of this family commonly have six pectoral fin muscles: the abductor superficialis, abductor profundus, arrector ventralis, adductor superficialis, adductor profundus, and arrector dorsalis. An additional muscle, the arrector medialis (named in this study), was discovered on the mesial side of the pectoral fin in all nine examined species of Synodus and Trachinocephalus, but is absent in all four examined species of Harpadon and Saurida. It inserts on an anterior process of the base of the mesial half of the uppermost ray and appears to have a function similar to that of the arrector ventralis in supporting the protraction of the uppermost ray and the abduction of the pectoral fin. This muscle supports the division of the synodontids into two groups (present in Synodus and Trachinocephalus vs absent in Harpadon and Saurida). The function of the arrector medialis is morphologically discussed.
Two specimens of a rare ophidiid fish, Barathrites iris Zugmayer, 1911, were collected from the abyssal Pacific Ocean, off Kagoshima Prefecture, southern Japan. They agree with the diagnosis of Barathrites in having two pelvic-fin rays, five to six long gill rakers on the anterior gill arch, and a small head (33.5-33.8% of pre-anal-fin length) and eye (1.6-1.8% standard length, SL). Additionally, they can be separated from B. parri Nybelin, 1957, the only other known species of the genus, by their lack of basibranchial tooth patches, smaller eye (10.7-12.3% head length), and shorter pre-dorsal-fin region (17.1-18.9% SL). Previously B. iris was said to differ from B. parri in the number of branchiostegal rays (six versus seven, respectively), but one of the present specimens of B. iris (413mm SL) has seven branchiostegal rays on the left side and six on the right. Earlier workers have suggested the occurrence of Barathrites in the Pacific Ocean, but no documented records from this ocean appear to exist. This study confirms the occurrence of Barathrites and its type species B. iris in the Pacific Ocean.
A new species of the pentodontine genus Dipelicus Hope is described from Wetar Island. Dipelicus fastigatoides sp. n. is similar externally to D. fastigatus Endrodi, 1969, but the two species can be distinguished easily from each other by the shape of the male parameres.
The genus Holopsis Broun, 1883 from Japan is revised. Five species including two newly recorded species and one new species are described: H. punctipennis (Matthews, 1899), H. kirejtshuki Bowestead, 2003 (new record), H. kurilensis Bowestead, 2003 (new record), H. lewisei Bowestead, 2003, and H. ryukyuensis sp. n. Males of H. punctipennis and H. lewisei are described for the first time.
The terrestrial amphipod genus Brevitalitrus Bousfield, 1971 (Talitridae) is represented by seven previously described species. In this study, two species of the genus are reported for the first time from Taiwan: B. hortulanus (Calman, 1912) collected from the terrestrial habitat of Green Island (=Lu Tao) and B. kumanoi sp. nov. from the coastal areas of Nan Bay of the mainland and Lanyu Island. Among its congeners, this latter species is most similar to B. nesius (Barnard, 1960) and B. toli (Barnard, 1960) in lacking marginal spines on the outer rami of uropods 1 and 2 and in having the propodus of pereopod 6 subequal in length to the basis. It differs from B. nesius in having the posterodistal lobe of the basis of pereopod 7 hardly incised at junction, the posterior margin of epimeral plate 3 gently convex, and the distolateral spine of uropod 1 simple, and from B. toli by the distally narrowing basis of pereopod 7, the rami of pleopod 2 that are shorter than the peduncle, and the tri-articulate rami of pleopod 3. Brevitalitrus kumanoi sp. nov. also differs from B. hortulanus in having the peduncle of pleopod 3 subequal in width to those of pleopods 1 and 2 and the outer rami of uropods 1 and 2 without marginal spines. Special attention is paid to the armature of the dactyli of pereopods 3-7 and the sub-categories of the cuspidactylate state. The terms uni-cuspidactylate and bi-cuspidactylate are proposed to better express the relationship of species in the genus. An identification key to all known species of the family Talitridae from Taiwan is provided.
Adults of caligiform copepods are often found in plankton samples, in addition to the naupliar and copepodid stages. Here, we report on adult parasitic copepods of the families Caligidae and Pandaridae from plankton samples collected in Japanese and Chinese coastal waters. The following previously described species were found in 2008: Caligus calotomi Shiino, 1954; C. orientalis Gusev, 1951; C. undulatus Shen and Li, 1959; Lepeophtheirus semicossyphi Yamaguti, 1939; Metacaligus uruguayensis Thomsen, 1949, and Pandarus satyrus Dana, 1852 in Japanese waters; and C. orientalis and C. rotundigenitalis Yu, 1933 in Chinese waters. The findings of adults of Lepeophtheirus and Metacaligus in plankton samples represent the first such a record for each genus. Two new species of Caligus are also described from plankton taken in Japanese waters in 2008 and 2010. An ovigerous female collected from off Iheya Island, Ryukyu Islands, Okinawa Prefecture is described as Caligus quadrigenitalis sp. nov., and two adult females and a male collected from the Seto Inland Sea and off Hirado Island, Kyushu, western Japan is described as Caligus ogawai sp. nov.
A new species of free-living marine nematode, belonging to the genus Micoletzkyia Ditlevsen, 1926 (Phanodermatidae Filipjev, 1927), is described from the deep sea off the coast of Hokkaido, northern Japan. Micoletzkyia mawatarii sp. nov. resembles M. magna Vitiello, 1970 and M. longispicula Huang and Cheng, 2012 in the shape of the tail and gubernaculum, but differs from the former in body width and in length of the cephalic setae, and from the latter in body length, proportional length of the tail, position of the nerve ring, and shape of the precloacal supplement. Micoletzkyia mawatarii sp. nov. also resembles M. parelegans Allgen, 1954 in its large body size, but differs from it in esophagus length, shape of the gubernaculum, size and position of the precloacal supplement, and in having a longer tail.
An octannulate Orobdella leech, Orobdella octonaria Oka, 1895, is redescribed on the basis of one syntype collected from Hakone, Kanagawa Prefecture, Japan, and two newly obtained specimens, also from Hakone. It is distinguished from the other known species of Orobdella by its octannulate mid-body somites. No holotype of this species was originally designated. The present syntype from Hakone is designated as the lectotype of O. octonaria for the purpose of clarifying its taxonomic status and type locality.
Specimens of the genus Orobdella Oka, 1895 from Gageodo Island, Korea, are identified as Orobdella tsushimensis Nakano, 2011 based on the following characteristics: IV uniannulate; 1/2+5 annuli between the gonopores; a bottle-shaped gastroporal duct; and epididymides in XVII-XIX. The diagnosis of O. tsushimensis is amended since the Korean specimens have a reddish dorsal surface and ovate atrial cornua. Phylogenetic analyses using mitochondrial COI, tRNA^<Cys>, tRNA^<Met>, 12S rRNA, tRNA^<Val>, and 16S rRNA markers show that the specimen from Gageodo Island and those identified as O. tsushimensis from Tsushima Island, Japan, form a monophyletic clade, confirming the species identification of the former. This is the first record of the genus Orobdella, and of the monotypic family Orobdellidae, from Korea.