Spicomacrurus Okamura, 1970

Schwarzhans, Werner, 2014, Head and otolith morphology of the genera Hymenocephalus, Hymenogadus and Spicomacrurus (Macrouridae), with the description of three new species, Zootaxa 3888 (1), pp. 1-73 : 19-20

Spicomacrurus Okamura, 1970

Spicomacrurus Okamura 1970: 63 , as subgenus of Hymenogadus Gilbert & Hubbs, 1920 , type species by original designation Hymenocephalus kuronumai Kamohara, 1938 .

Hymenocephalus (Spicomacrurus) : Iwamoto & Merrett 1997: 514.

Spicomacrurus: Iwamoto, Shao & Ho, 2011: 514 .

Diagnosis. Modified from Iwamoto et al. (2011) Leading spine of dorsal fin smooth. Ventral striae consisting of fine parallel lines of dark, alternating with silvery pigment associated with light-producing function on abdominal wall, parts of chest, and shoulder girdle, not joint at median line behind pelvic fin bases. Head not cavernous. Nasal bones forming broad, horizontal, lateral, and medial plate-like processes; nasal bones of both sides in broad contact (two species), or widely separated by rostral cartilage (two species). Gill rakers 9–15. Additional diagnostic features from otolith morphology are: Elongate shape of otoliths (OL:OH = 1.45–1.95); otoliths thin due to slightly concave outer face; relatively low and short predorsal lobe; ventral sulcus margin at collum indented; pseudocolliculum indistinct, short.

Comparison. Spicomacrurus is remarkable for the spectacular specialization of its broad spatulate nasal bones (see above). It further differs from the related genera Hymenogadus and Hymenocephalus by the lack of the cavernous cephalic canal system covered by thin skin (integument). It shares with Hymenogadus the short ventral striae, which are not joined along the mesial line behind the pelvic fin bases, and the rather slender otoliths with the narrow, ventrally indented collum and the short pseudocolliculum.

Species. Four species, all from the western Pacific, S. adelscotti , S. dyctiogadus , S. kuronumai and S. mccoskeri .