Head and otolith morphology of the genera Hymenocephalus, Hymenogadus and Spicomacrurus (Macrouridae), with the description of three new species Author Schwarzhans, Werner text Zootaxa 2014 2014-11-28 3888 1 1 73 journal article 10.11646/zootaxa.3888.1.1 1175-5326 10086415 1B437AE1-CF28-4C1B-95B6-C31A295905A0 Hymenocephalus papyraceus Jordan & Gilbert, 1904 Figs. 14F–J , 16 Hymenocephalus papyraceus Jordan & Gilbert, 1904: 614 ( type locality: Sagami Bay , Japan ). Hymenocephalus papyraceus : Okamura, 1970: 56 . Material examined. 12 specimens ; 6 specimens BSKU 44292-44297 , 120 + –132+ mm TL, central Tosa Bay off Kochi , 600 m ; 1 specimen BSKU 44761, 170 mm TL, central Tosa Bay off Kochi , 600 m ; 1 specimen BSKU 99483, 171 mm TL, off southern Japan (no further data) ; 1 specimen BSKU 101959 , R / V Hakuro-maru (KH 73-2, St. 4); BSKU NMIC-ZF-03092 , 147 mm TL, off southern Japan (no further data) ; 1 specimen USNM 50935 ( holotype ), 112 mm TL, Sagami Bay , 220–485 m ; 1 specimen ZMMGU P-18258, 30°30’N , 129°19’E . Diagnosis. Pelvic fin rays 10–11; pectoral fin rays 16–18; snout projecting, with thin, pointed tip, 20–25% HL; barbel short, 4–5% HL, not reaching vertical through anterior margin of orbit; orbit diameter moderate, 25–30% HL; interorbital width 70–80% HW; infraorbital width 16–20% HL; preopercular supporter very long, straight, 10–11% HL; gill rakers 18–22; ventral striae reaching to about ⅓ distance from pelvic fin bases to periproct; otolith with moderately high predorsal lobe, colliculi separated, closely placed across narrow collum, terminating far from anterior and posterior rims of otolith; OL:OH = 1.05; TCL:PCL = 2.1. Comparison. Hymenocephalus papyraceus resembles H. aterrimus and H. neasaeae . From H. aterrimus it differs in the number of pelvic and pectoral fin rays (10–11 vs 13–14 and 16–18 vs 13–16, respectively), the smaller preopercular canal width (14–17 vs 19–23% HL), the smaller postorbital-preopercular interspace (4–6 vs 10–14% HL), the long and slender preopercular supporter (11 vs 3–4% HL) and the otolith with a distinct predorsal lobe. For difference with H. nesaeae see above. Description. Head morphology (n = 3) ( Fig. 14F–H ): Head large, snout projecting, long, with thin pointed tip, which is easily damaged, snout length 20–25% HL, orbit diameter 25–30% HL, interorbital width 70–80% HW. Barbel short, 4–5% HL, not reaching vertical through anterior margin of orbit. Head canals well developed, large, infraorbital width 16–20% HL, supraorbital canal with 4 segments, width 17–20% HL, supratemporal canal rather distinct and wide, above segment 3 of supraorbital canal, preopercular canal width 14–17% HL, postorbitalpreopercular interspace 4–6% HL. Infranasal supporter small; infraorbital supporter short, expanding only beyond rear part of orbit, 40–60% OD; preopercular supporter very long, thin and straight (11% HL). Otolith morphology (n = 1) ( Fig. 14I–J ): Otolith moderate in size, ventrally well rounded, dorsally with a distinct predorsal lobe, postdorsally somewhat undulating and regularly inclined towards rounded posterior tip; OL:OH = 1.05; OH:OT = 3.5. Inner face slightly convex, with median sulcus. Ostial and caudal colliculi small, narrowly placed across collum, terminating at considerable distance from anterior and posterior tips of otolith; pseudocolliculum moderately short. CCL:OCL = 0.85; TCL:PCL = 2.1. Dorsal depression small; ventral furrow distinct, moderately close to ventral rim, anteriorly and posteriorly turning away and upwards. Distribution ( Fig. 16 ). Hymenocephalus papyraceus is only known off the southeastern coast of Japan , chiefly the Sagami and Tosa Bays and off Kagoshima .