longiceps, Hymenocephalus Smith [H. M.] & Radcliffe [L.] in Radcliffe 1912:111, Pl. 23 (fig. 3) [Proceedings of the United States National Museum v. 43 (no. 1924); ref. 3578] Off southeastern Luzon Island, 13°10'21"N, 123°59'54"E, Philippines, Albatross station 5459, depth 201 fathoms. Holotype: USNM 72928. Paratypes: USNM 149297 (2). First author is H. M. Smith. •Valid as Hymenocephalus longiceps Smith & Radcliffe 1912 -- (Yatou in Okamura et al. 1982:141, 346 [ref. 8256], Okamura in Masuda et al. 1984:93 [ref. 6441], Okamura in Okamura & Kitajima 1984:199, 357 [ref. 8057], Paxton et al. 1989:327 [ref. 12442], Iwamoto in Cohen et al. 1990:230 [ref. 18936], Iwamoto & Williams 1999:177 [ref. 23875], Nakabo 2000:419 [ref. 25086], Iwamoto in Randall & Lim 2000:595 [ref. 25122], Hutchins 2001:24 [ref. 25847], Shinohara et al. 2001:305 [ref. 25995], Nakabo 2002:419 [ref. 26001], Shinohara et al. 2005:417 [ref. 28370], Motomura et al. 2015:16 [ref. 34709], Iwamoto et al. 2015:75 [ref. 35408]). •Synonym of Hymenocephalus longibarbis (Günther 1887) -- (Schwarzhans 2014:27 [ref. 33586], Nakayama 2020:215 [ref. 37888]). Current status: Synonym of Hymenocephalus longibarbis (Günther 1887). Macrouridae. Habitat: marine.