Synopsis of the Grenadier Fishes (Gadiformes; Teleostei) of Taiwan Author Iwamoto, Tomio Section of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA; Author Nakayama, Naohide Laboratory of Marine Biology, Faculty of Science, Kochi University, 2 - 5 - 1 Akebono-cho, Kochi, 780 - 8073, Japan; Author Shao, Kwang-Tsao Research Center for Biodiversity, Academia Sinica No. 128, Sec. 2, Academia Road, Nankang, Taipei 115, Taiwan; Author Table, Hsuan-Ching Ho text Proceedings of the California Academy of Sciences 2015 2015-04-15 62 3 31 126 journal article 299670 10.5281/zenodo.11512126 522b8de7-880d-40ca-803e-aa5a3a05c5f6 0068-547X 11512126 Genus Hymenocephalus Giglioli, 1882 DISTINGUISHING FEATURES .— Snout high, relatively rounded, median nasal process forming a weak snout tip (no horizontal platelike process mesially); paired nasal bone in broad contact along median line, without wide gap around nostril cartilage; head much deeper than wide; body relatively compressed; head mucous canals greatly expanded; head covering membranous and often transparent; light organ long, small lens on chest anterior to pelvic-fin bases connected by a black streak to round posterior lens immediately before anus; ventral striae well developed; fine black lines on gular membrane oriented perpendicular to median line, not netlike; inner GR-I, lower limb 12–16; spinous ray of 1D completely smooth; chin barbel present or absent. REMARKS .— A genus of about 20 species, four of which are known from Taiwan . Most species do not exceed about 20 cm TL. The highly developed luminescent organ system consisting of a network of fine striations (“ventral striae”) on the cleithrum, chest, and belly regions is seen in gadiforms only in this genus, its closely related genera Hymenogadus and Spicomacrurus , and the monotypic genera Steindachneria Goode and Bean in Agassiz, 1888 and Lepidorhynchus Richardson, 1846 . The presence of two lens-like bodies of the light organ, one on the chest, the other immediately before the anus, is unique among the grenadiers to Hymenocephalus , Hymenogadus , and Spicomacrurus . The position of the lenses is similar to that of the ventral fossae of some species of Coelorinchus , but so far as we can determine, there are no comparable structures in that or other grenadiers. The delicate, paper-thin head bones and membranous head integument are usually damaged during capture, adding to the difficulties of identifying specimens.