Sebastes pachycephalus

discussion

Remarks. Counts and measurements of the hybrid specimens are shown in Tables 2 and 3 respectively. On the basis of genetic and morphological analyses, FAKU 85922 and 86957, and NMCI – P. 1527 were shown by Kai et al. (2011) to be hybrids of S. pachycephalus and S. nudus. FAKU 85922 had minute scales below the entire dorsalfin spine base and dark spots the prepelvic region. Accordingly, Kai et al. (2011) initially identified the specimen as S. p. pachycephalus sensu Matsubara (1943) (= S. pachycephalus here). Similarly, FAKU 86957 and NMCI – P. 1527 had minute scales below the entire dorsal-fin spine base but lacked dark spots on the prepelvic region, and Kai et al. (2011) initially identified them as S. p. nigricans sensu Matsubara (1943) (= S. pachycephalus here). However, a principal co-ordinate analysis using genetic data indicated that all three specimens occupied intermediate positions between the two species. A principal component analysis based on morphometric characters also indicated that they occupied equivocal positions in Kai et al. (2011). Accordingly, they were judged to be hybrids (Kai et al. 2011). Although no genetic data was available for FAKU 6319 and FAKU 41980,

Taxonomic review of the Sebastes pachycephalus complex (Scorpaeniformes: Scorpaenidae)

materials_examined

Materials examined. 5 specimens, 119.0 – 173.2 mm SL, all from Japan: FAKU 6319, 119.0 mm SL, Shimonoseki, Yamaguchi; FAKU 41980, 173.2 mm SL, Maizuru, Kyoto; FAKU 85922, 86957, NMCI – P. 1527, 122.7 – 128.8 mm SL [3 specimens; all genetically identified as hybrids in Kai et al. (2011)], Noto, Ishikawa, coll. Y. Kai and K. Sakai.

Taxonomic review of the Sebastes pachycephalus complex (Scorpaeniformes: Scorpaenidae)

description

Description. Measurements as percentages of SL of the specimens examined are given in Table 1. Selected counts are given in Table 2. Body relatively deep, moderately compressed anteriorly, progressively more compressed posteriorly. Nape and anterior body moderately convex. Tentacles absent on head and body, except for nostril tentacle. Head completely covered with ctenoid scales, except for tip of snout, maxillary, lacrimal, lower jaw, interopercle, and branchiostegal rays. Posterior part of maxillary sometimes with minute embedded scales. Body covered with ctenoid scales usually with some accessory scales in posterior field, except for pectoral fin base, prepelvic region and ventral abdominal surface. Embedded cycloid scales covering pectoral fin base and prepelvic region; remaining ventral abdominal surface completely covered with minute cycloid scales. Base of entire spinous portion of dorsal fin densely covered with minute scales, usually extending onto basal spines and membranes (Fig. 2 A); anterior part of spinous portion of base sometimes with very narrow naked area in smaller specimens (under ca. 60 mm SL). Patches of minute scales sometimes on membrane of spinous dorsal fi

Taxonomic review of the Sebastes pachycephalus complex (Scorpaeniformes: Scorpaenidae)

description

Sebastes (Murasoius) pachycephalus, form. pachycephalus: Matsubara 1943: 239, pl. II- 1 (Chiba, Kanagawa, Aichi, Wakayama, and Kobe, Japan). Sebastes (Murasoius) pachycephalus, form. nigricans: Matsubara 1943: 242, pl. III- 1 (Shimonoseki and Nagasaki, Japan). Sebastes pachycephalus complex " Species P-Ni ": Kai et al. 2011: 340 (Nagasaki, Shimane, Fukui, Ishikawa, Hiroshima, Wakayama, and Fukushima, Japan). Sebastes pachycephalus pachycephalus: Matsubara 1955: 1077, key, fig. 377 [after Matsubara (1943)] (Chiba southward to Kyushu, Japan, Busan, Korea, and China); Hiyama & Yasuda 1961: 112, pl. 148 (in part?, Hokkaido southward to Kyushu, Japan and southern Korea); Matsubara 1965: 426, unnumbered fig. [after Matsubara (1943)] (Aomori southward to Kyushu, Japan, Busan, Korea, and China); Kanayama & Kitagawa 1982: 42, unnumbered fig. (Iwate, Japan); Lindberg & Krasyukova 1987: 75, fig. 32 [after Matsubara (1943)] (Yokohama and Nagasaki, Japan and Busan, Korea); Nakabo 1993: 518, key (Chiba southward to Kyushu, Japan, Busan, Korea, and Yellow Sea); Masuda & Kobayashi 1994: 85, figs. 3 – 4 (Izu, Japan); Nakabo 1995: 177, color photo (Shimane, Japan); Motomura & Iwatsuki 1997: 130 (Nan

Taxonomic review of the Sebastes pachycephalus complex (Scorpaeniformes: Scorpaenidae)