Lepadichthys misakius ( Tanaka 1908 )

Fujiwara, Kyoji & Motomura, Hiroyuki, 2019, Validity of Lepadichthys misakius (Tanaka 1908) and redescription of Lepadichthys frenatus Waite 1904 (Gobiesocidae: Diademichthyinae), Zootaxa 4551 (3), pp. 275-298 : 279-288

Lepadichthys misakius ( Tanaka 1908)

[New English name: Northern Bridled Clingfish; standard Japanese name: Misaki-ubauo]

Figures 3C, D , 4 D–F, 6B, 7, 9–14, 15A–H, 16, 17; Tables 1–2

Aspasma misakia Tanaka 1908: 22 (type locality: Misaki, Miura, Kanagawa, Japan); Snyder 1912a: 447 (Tanega-shima island, Kagoshima and Kanagawa, Japan); Snyder 1912b: 517, pl. 69, fig. 3 (Okinawa, Japan: based on 12 specimens); Jordan et al. 1913: 378 (southern Japan); Schmidt 1930: 133 (Okinawa, Japan); Okada 1938: 249 (southern Japan); Okada & Matsubara 1938: 378, pl. 89, fig. 3 [southern Japan: photograph from Snyder (1912b)]; Matsubara et al. 1949: 320, fig. 924 (southern Japan); Tanaka 1951: 58, pl. 15, fig. 50 (Kanagawa, Japan); Matsubara 1955: 1216 (southern Japan); Matsubara 1979: 1216 (southern Japan).

Lepadichthys frenatus (not of Waite): Briggs 1955: 139 [in part; Chiba, Japan (based on 7 specimens, SU 47726–7), Kanagawa, Japan (based on 11 specimens, UMMZ 162003–4, SU 22569, 47681), Shimane, Japan (based on 2 specimens, UMMZ 162005, 162008), Okinawa, Japan (based on USNM 162005)]; Shiogaki & Dotsu 1971: 86, fig. 1 (Nagasaki, Japan); Arai & Ida 1975: 197 [Yaku-shima island, Kagoshima, Japan (based on 3 specimens, NSMT-P 58109, 58118, 58121)]; Masuda et al. 1975: 348, pl. 150E (southern Japan); Yoshino 1984: 327, pl. 306H [southern Japan: photograph from Masuda et al. (1975)]; Hayashi & Hayashi 1985: 56 [in part; Shizuoka, Japan (based on YCM-P 12762), Miyake-jima island, Izu Islands, Japan (based on 2 specimens, TMBS 730728–1, 730923–1), Ehime, Japan (based on YCM-P 15103), Okinawa, Japan (based on 23 specimens, URM-P 9230–9240)]; Hayashi 1993: 410, unnumbered fig. (southern Japan and Ogasawara Islands, Japan); Masuda & Kobayashi 1994: 57, fig. 3 (Izu Peninsula, Japan); Lindberg et al. 1997: 196, fig. 129 [Sea of Japan: photograph from Snyder (1912b)]; Okamura 1997: 572, unnumbered figs. (Izu-oshima island, Izu Islands, Japan); Hayashi 2000: 1123, unnumbered fig. (southern Japan and Ogasawara Islands, Japan); Hutchins 2000: 598 (South China Sea); Shinohara et al. 2000: 181 [Tokushima, Japan (based on 11 specimens, NSMT-P 59457, 59469, 59474, 59495, TKPM-P 7979, 9205)]; Hayashi 2002: 1123, unnumbered fig. (southern Japan and Ogasawara Islands, Japan); Motomura et al. 2010: 200, fig. 472 [Yaku-shima island, Kagoshima, Japan (based on 17 specimens, BSKU 96653, 96654, FRLM 34741, KAUM–I. 11163, 11266, 11330, 11621, 20276, 21757, 21758, 21832, MUFS 25605–25607, NSMT-P 91670, 91671, 95455, plus those listed in Arai & Ida 1975)]; Takagi et al. 2010: 121, unnumbered figs. (Ehime, Japan); Wang 2011: 132, pl. 132, figs. 434-1a, b (Taiwan); Hayashi & Hagiwara 2013: 1328, unnumbered fig. (southern Japan); Haraguchi 2014: 485, unnumbered fig. [Yoron-jima island, Kagoshima, Japan (based on KAUM–I. 40010)]; Kato 2014: 295, unnumbered fig. (Izu Peninsula, Japan); Murase 2015: 5, fig. 8C [Yaku-shima island, Kagoshima, Japan (based on 3 specimens, KPM-NI 29643, 29682, 29695)]; Iwatsubo et al. 2016: 57, unnumbered fig. [Kagoshima, Japan (based on KAUM–I. 56686)]; Motomura & Harazaki 2017: 115 [Yaku-shima island, Kagoshima, Japan (based on 5 specimens, KAUM–I. 38398, 38399, 41853, NSMT-P 104199, 104208, plus those listed in Arai & Ida 1975, Motomura et al. 2010 (except for KAUM–I. 11266) and Murase 2015)]; Conway et al. 2017b: 142, fig. 1 [ Japan (based on JFBM 46744 and KPM-NR 26999)]; Kimura et al. 2017: 155, fig. 7 [Kuchino-shima island, Kagoshima Japan (based on KPM-NI 41432)]; Fujiwara 2018: 324, unnumbered figs. [Amami Islands, Kagoshima, Japan (based on 3 specimens, KAUM–I. 79067, 40010, 62636)].

Lepadichthys coccinotaenia (not of Regan): Motomura & Aizawa 2011: 456 [Yaku-shima island, Kagoshima, Japan (based on KAUM–I. 11266)]; Motomura & Harazaki 2017: 115 [Yaku-shima island, Kagoshima, Japan (based on specimen listed in Motomura & Aizawa 2011)].

Holotype. ZUMT 1981 , 51.9 mm SL, Misaki, Miura, Kanagawa Pref., Japan, S. Tanaka, May 1908.

Non-type specimens. 82 specimens, 14.6–57.7 mm SL. JAPAN: Boso Peninsula: CMNH-ZF 4486 , 14.8 mm SL, Hasama Fish Port, Hasama, Tateyama , Chiba Pref. , 34°58′30″N, 139°47′00″E, hand net, M. Aizawa, 13 Nov. 2002; CMNH-ZF 7630 , 37.8 mm SL, Isomura, Kamogawa, Chiba Pref. , 35°05′22″N, 140°07′17″E, hand net, M. Aizawa, 5 Mar. 2004; CMNH-ZF 11378 , 44.6 mm SL, CMNH-ZF 11379 , 43.3 mm SL, CMNH-ZF 11380 , 39.2 mm SL, Isomura, Kamogawa, Chiba Pref. , 35°05′20″N, 140°07′15″E, hand net, M. Aizawa, 23 July 2004 ; CMNH- ZF 11393, 41.3 mm SL, Ubara-jima island, Ubara, Katsuura , Chiba Pref. , 35°07′28″N, 140°16′58″E, hand net, M. Aizawa, 27 July 2004; CMNH-ZF 12053 , 23.8 mm SL, Okino-shima island, Fujimi, Tateyama , Chiba Pref. , 34°59′17″N, 139°49′46″E, hand net, M. Aizawa & Y. Ikeda, 16 Nov. 2004; CMNH-ZF 12091 , 40.1 mm SL, Igaijima island, Isomura, Kamogawa , Chiba Pref. , 35°05′18″N, 140°07′13″E, hand net, M. Aizawa, 9 Dec. 2004; CMNH-ZF 12210 , 45.8 mm SL, Ubara, Katsuura, Chiba Pref. , 35°07′00″N, 140°16′58″E, hand net, M. Aizawa, 3 Mar. 2005; CMNH-ZF 12229 , 53.8 mm SL, Hasama, Tateyama, Chiba Pref. , 34°58′44″N, 139°46′54″E, hand net, M. Aizawa, 9 Mar. 2005; CMNH-ZF 12460 , 30.8 mm SL, CMNH-ZF 12461 , 48.2 mm SL, Isomura, Kamogawa, Chiba Pref. , 35°05′16″N, 140°07′11″E, hand net, M. Aizawa, 23 Apr. 2005; CMNH-ZF 13409 , 50.0 mm SL, Isomura, Kamogawa, Chiba Pref. , 35°05′22″N, 140°07′17″E, hand net, M. Aizawa, 11 Aug. 2005; CMNH-ZF 14331 , 48.8 mm SL, Okino-shima island, Fujimi, Tateyama , Chiba Pref. , 34°59′17″N, 139°49′46″E, hand net, M. Aizawa & Y. Ikeda, 22 Nov. 2005; CMNH-ZF 15273 , 57.7 mm SL, Igai-jima island, Isomura, Kamogawa , Chiba Pref. , 35°05′18″N, 140°07′13″E, hand net, M. Aizawa, 21 June 2006; CMNH-ZF 15722 , 36.8 mm SL, Hasama, Tateyama, Chiba Pref. , 34°58′42″N, 139°47′33″E, hand net, M. Aizawa, 28 July 2006. Suruga Bay : CMNH-ZF 30 , 39.2 mm SL, CMNH-ZF 31 , 44.9 mm SL, CMNH-ZF 32 , 53.3 mm SL, Matsuzaki, Kamo, Shizuoka Pref. , 35°43′45″N, 138°44′30″E, hand net, M. Aizawa, 23 Dec. 1994; CMNH-ZF 16026 , 53.7 mm SL, Shishihama, Numazu, Shizuoka Pref. , 34°58′42″N, 139°47′33″E, hand net, M. Aizawa, 28 July 2006; NSMT-P 62108 , 51.3 mm SL, Ryugu-jima island, Shimoda, Shizuoka Pref. , hand net, 3–5 m, S. Takahashi, 21 Dec. 2001. Izu Islands : NSMT-P 30823 , 43.6 mm SL, Awabe, Miyake-jima island , 34°02′42″N, 139°29′48″E, 23 Sept. 1973; NSMT-P 30824 , 38.2 mm SL, Kamakata, Miyake-jima island , 34°03′36″N, 139°33′42″E, 28 July 1973. Shikoku: BSKU 51019 , 36.1 mm SL, Shiranohana, Tosa, Kochi Pref. , 26 June 2006; BSKU 51020 , 48.2 mm SL, Shiranohana, Tosa, Kochi Pref. , 28 July 2006; BSKU 54985 , 47.7 mm SL, Shiranohana, Tosa, Kochi Pref. , 11 Sept. 2006; BSKU 65523 , 35.7 mm SL, Shiranohana, Tosa, Kochi Pref. , 4 Apr. 1996; BSKU 72044 , 26.1 mm SL, Shiranohana, Tosa, Kochi Pref. , 20 Oct. 2006; BSKU 95784 , 20.8 mm SL, Moshima Port, Okino-shima island, Kochi Pref. , 22 July 2008; BSKU 100025 , 41.4 mm SL, Okino-shima island, Kochi Pref. , hand net, 23 Sept. 2009; BSKU 100141 , 48.6 mm SL, Okino-shima island, Kochi Pref. , 25 Sept. 2009; BSKU 103919 , 21.0 mm SL, BSKU 103920 , 16.5 mm SL, Kuboura, Okino-shima island, Kochi Pref. , 21 July 2010; BSKU 108061 , 23.3 mm SL, Moshima Port, Okinoshima island, Kochi Pref. , hand net, 6 m, 23 July 2012; BSKU 109521 , 15.6 mm SL, Kuboura, Okino-shima island , Kochi Pref., 23 July 2008; NSMT-P 59474 , 51.0 mm SL, I-shima island, Anan, Tokushima Pref. , 33°51′00″N, 134°48′36″E, hand net, 6 m, K. Matsuura & G. Shinohara, 29 Oct. 1999; NSMT-P 97274 , 37.0 mm SL, Mugioshima island, Kaifu, Tokushima Pref. , beach seine, 7 m, K. Matsuura & M. Aizawa, 28 Oct. 1994. Kyushu: CMNH-ZF 12753 , 25.3 mm SL, Tatunokuchi, Kouyagi, Nagasaki Pref. , hand net, Y. Ikeda & M. Aizawa, 13 May 2005; KAUM–I . 8806, 49.3 mm SL, Nagasakibana, Ichiki-kushikino, Kagoshima Pref. , 31°42′24″N, 130°15′44″E, hand net, 0.1–0.5 m, H. Iwatsubo & G. Ogihara, 20 Mar. 2008; KAUM–I . 39316, 42.2 mm SL, Kushi, Minamisatsuma, Kagoshima Pref. , 31°17′22″N, 130°12′45″E, hand net, 1 m, H. Iwatsubo, 2 July 2011; KAUM–I . 56686, 41.5 mm SL, off Bandokorobana National Park, Minami-kyushu, Kagoshima Pref. , 31°14′N, 130°25′E, hand net, 2 m, H. Iwatsubo, 22 Sept. 2013; KAUM–I . 200596, 45.6 mm SL, Maruki Beach, Kushi, Minami-satsuma , Kagoshima Pref. , 31°17′05″N, 130°12′36″E, hand net, 0.1 m, H. Iwatsubo, 14 Apr. 2017. Osumi Islands : BSKU 96653 , 40.9 mm SL, Isso, Yaku-shima island , hand net, 31 Oct. 2008; CMNH-ZF 10455 ,

14.7 mm SL, Motoura, Yaku-shima island, 30°27′02″N, 130°29′57″E, hand net, Y. Ikeda & M. Aizawa, 8 May 2004; CMNH-ZF 15415 , 2 , 20.1 – 21.2 mm SL , CMNH-ZF 15660 , 17.6 mm SL, Isso, Yaku-shima island , 30°27′26″N, 130°29′45″E, hand net, Y. Ikeda & M. Aizawa, 12 July 2006 ; KAUM–I. 11163, 28.5 mm SL, Kurio, Yaku-shima island , 30°15′57″N, 130°24′52″E, hand net, 3 m , KAUM Fish Team , 10 Aug. 2008 ; KAUM–I. 11266, 49.1 mm SL, Yudomari Port, Yaku-shima island , 30°13′58″N, 130°28′19″E, hand net, 3 m , KAUM Fish Team , 11 Aug. 2008 ; KAUM–I. 11330, 24.6 mm SL, Tashiro Beach, Funayuki, Yaku-shima island , 30°21′02″N, 130°39′58″E, hand net, 0.5 m , KAUM Fish Team , 11 Aug. 2008 ; KAUM–I. 11621, 44.6 mm SL, Haruta Beach, Anbo, Yaku-shima island , 30°18′02″N, 130°39′17″E, hand net, 0.5–1.5 m, M. Meguro, 18 Aug. 2008 ; KAUM–I. 20276, 36.3 mm SL, Kurio, Yaku-shima island , 30°16′02″N, 130°39′17″E, hand net, 0.5–1.5 m , KAUM Fish Team , 30 Oct. 2008 ; KAUM–I. 21552, 48.3 mm SL; Ushino, Minamitane, Tanega-shima island , 30°26′32″N, 130°51′11″E, hand net, 0.3 m, H. Iwatsubo, 5 Aug. 2009 ; KAUM–I. 21757, 29.1 mm SL, KAUM–I. 21758, 32.4 mm SL, Kurio, Yaku-shima island , 30°15′57″N, 130°51′11″E, hand net, 2 m, G. Ogihara et al., 27 July 2009 ; KAUM–I. 21832, 30.3 mm SL, Kurio, Yaku-shima island , 30°16′03″N, 130°24′48″E, hand net, 4 m , KAUM Fish Team , 30 July 2009 ; KAUM–I. 36909, 53.7 mm SL, Onoma, Yaku-shima island , 30°14′N, 130°33′E, hand net, 13 Oct. 1988 ; KAUM–I. 38398, 22.4 mm SL, KAUM–I. 38399, 14.6 mm SL, Yudomari Port, Yaku-shima island , 30°13′55″N, 130°28′19″E, hand net, 1.0–5.0 m , KAUM Fish Team , 10 June 2011 ; KAUM–I. 41853, 42.0 mm SL, Shitoko, Yaku-shima island , 30°27′02″N, 130°30′54″E, hand net, 5 m , KAUM Fish Team , 18 Oct. 2011 . Tokara Islands : KAUM–I. 114855, 16.0 mm SL, Kiriishi Port, Suwanose-jima island , 29°36′38″N, 129°42′41″E, hand net, 3–7 m, S. Tashiro et al., 27 Apr. 2018 . Amami Islands : CMNH-ZF 6206 , 27.2 mm SL , CMNH-ZF 6207 , 24.8 mm SL, Ankyaba, Amami-oshima island , 28°28′17″N, 129°35′55″E, hand net, Y. Ikeda & M. Aizawa, 12 July 2003 ; CMNH-ZF 6309 , 23.3 mm SL, Ayamaruzaki, Amami-oshima island , 28°28′15″N, 129°43′23″E, hand net, Y. Ikeda, 14 July 2003 ; CMNH-ZF 6382 , 25.6 mm SL , CMNH-ZF 6383 , 24.8 mm SL, Kaseken, Amami-oshima island , 28°23′35″N, 129°36′52″E, hand net, Y. Ikeda & M. Aizawa, 15 July 2003 ; CMNH-ZF 6550 , 26.1 mm SL, Ayamaruzaki, Amami-oshima island , 28°28′20″N, 129°43′19″E, hand net, M. Aizawa, 14 July 2003 ; CMNH-ZF 7652 , 20.1 mm SL, Kaseken, Amami-oshima island , 28°23′34″N, 129°36′55″E, hand net, Y. Ikeda & M. Aizawa, 16 July 2003 ; KAUM–I. 17522, 37.4 mm SL, KAUM–I. 17580, 38.5 mm SL, KAUM–I. 17581, 47.1 mm SL, Kasari, Amami-oshima island , 28°24′34″N, 129°40′31″E, hand net, 0.5–1.0 m, M. Meguro & T. Yoshida, 28 Mar. 2009 ; KAUM–I. 40010, 22.6 mm SL, Mugiya, Yoron-jima island , 27°01′18″N, 128°26′21″E, hand net, 0.5–1.0 m, M. Matsunuma, 13 Aug. 2011 ; KAUM–I. 62636, 21.5 mm SL, Setouchi, Amami-oshima island , 28°11′38″N, 129°13′21″E, hand net, 5–13 m, K. Hagiwara et al., 26 June 2014 ; KAUM–I. 79067, 27.2 mm SL, Ayamarumisaki, Amami-oshima island , 28°28′28″N, 129°43′09″E, hand net, 0.5 m, K. Hagiwara et al., 21 July 2015 . Okinawa Islands : NSMT-P 121141 , 26.2 mm SL, Nago Bay, Nago, Okinawa-jima island , hand net, 1.0 m, K. Shibukawa, 24 Aug. 2014 . Ogasawara Islands : NSMT-P 63067 , 25.6 mm SL, Miyano Beach, Chichi-jima island , 3.0 m, K. Shibukawa, 17 Feb. 1995 . TAIWAN: ASIZP 57057 , 51.5 mm SL, Taipei, 25°30′N, 121°36′E, W.- H. Ding, 27 Aug. 1969 ; ASIZP 57058 , 2 , 38.5 – 53.3 mm SL, Yeliu , Taipei, 25°12′N, 121°41′E, S.- C. Lee, 20 May 1975 ; ASIZP 74064 , 57.5 mm SL, Badouzi , Keelung, 25°08′N, 121°47′E, S.- C. Lee, 26 Aug. 1969 . VIETNAM: ROM 73450, 31.6 mm SL, ROM 74260, 19.1 mm SL, Nha Trang Bay , Khánh Hòa, 12°10′N, 109°18′E, hand net, R. Winterbottom et al., 22 May 2002 .

Diagnosis. A species of Lepadichthys characterized by the following combination of characters: 15–19 (modally 16) dorsal-fin rays; 12–14 (13) anal-fin rays; 25–28 (26 or 27) pectoral-fin rays; upper end of gill membrane level with 5th to 8th (usually 6th) pectoral-fin ray base in lateral view; lower 8th to 11th (9th) pectoralfin ray base attached to disc base by membrane; 7–11 (9) gill rakers on each arch; head width moderate, its width 17.1–21.9 (mean 19.1) % SL; disc size moderate, its length 16.3–20.8 (18.5) % SL; anterior, posterior and least interorbital widths 9.0–11.8 (10.7), 13.4–16.9 (15.3) and 3.2–8.8 (6.2) % SL, respectively; dorsal, anal and caudal fins connected by membranes; NC2 (nasal canal pore) usually located between anterior and posterior margins of posterior nostril; and black stripe on snout tip through eye to posterior region of head.

Description. Measurements and counts are given in Tables 1 and 2, respectively. Body slender, cylindrical, compressed at caudal peduncle ( Figs. 9 , 10 ). Head of medium size, depressed anteriorly, its length and width 2.9 (2.5–3.3) and 5.2 (4.6–5.9) in SL, respectively. Snout moderate, its length 9.8 (7.9–11.8) in SL, tip slightly rounded (bluntly pointed) in lateral view, duck beak-shaped in dorsal view; dorsal profile of snout slightly concave anteriorly. Anterior and posterior nostrils similarly sized, both with a membranous tube, that of former much longer than latter; both visible in lateral view, former located between verticals through posterior point of upper jaw and anterior margin of eye, latter located directly above anterior margin of eye. Eye size moderate, diameter less than snout length, 15.4 (9.1–16.9) in SL. Interorbital region flattened. Anus closer to anal-fin origin than to posterior margin of disc.

Mouth terminal. Upper jaw slightly longer than lower jaw, upper-jaw length 10.2 (8.8–12.9) in SL. Anterior tip of upper jaw extending beyond that of lower jaw; posterior tips of both jaws horizontally level with lower margin of eye (slightly below horizontal level). Upper-jaw lip slightly thicker than lower-jaw lip. Single row of small similarly-sized teeth in both jaws; upper-jaw teeth incisiviform, tips strongly (almost 90 o) curved posteriorly; lower-jaw teeth with pointed conical tips. Premaxillae separated anteriorly by large circular gap in dorsal view ( Fig. 11A, D ). First to third gill arches with two rows of gill filaments [3 gills (sensu Briggs 1955)], 4th arch without filaments. Gill rakers slender, elongate, somewhat pointed. Gill membranes on each side united ventrally, attached to isthmus.

Dorsal and anal fins long, located posteriorly, their lengths 2.9 (2.9–4.3) and 3.4 (3.3–4.8) in SL, respectively. Origin of dorsal fin slightly anterior to vertical through anal-fin origin. First dorsal- and anal-fin rays very short, sometimes buried under skin. Dorsal- and anal-fin heights almost equal, except anteriorly. Pectoral- and caudal-fin margins rounded. Upper and lowermost pectoral-fin rays minute; longest pectoral-fin ray extending beyond vertical through posterior margin of disc, its length 6.1 (5.7–7.7) in SL. All soft-fin rays unbranched. Principal caudal-fin rays segmented. Second preural centrum with two (one) neural spines ( Fig. 3C, D ).

Pelvic fins and pectoral-girdle elements forming a circular “single” type disc, its length and width 5.5 (4.8–6.2) and 5.8 (5.1–7.0) in SL, respectively. Disc region B bell-shaped, same size as disc region A. No disc region C. Anterior and posterior margins of disc regions A and B, respectively, with fringe, latter much longer than former (holotype damaged). Disc regions A and B with flattened papillae (holotype damaged); anterior part of disc region A with 2–7 rows of papillae across center (center without papillae in 31 of 54 specimens), both sides of disc region A (except margins) completely covered with papillae, inner rows somewhat larger than outer rows; disc region B with 4–10 rows of papillae, inner rows somewhat larger than outer rows, anterior part of disc region B without papillae ( Fig. 4 D–F).

Head sensory canal pores well-developed, including 2 nasal, lacrimal and postorbital and 3 preopercular pores ( Fig. 12 ); mandibular canal pores absent. All pores similarly sized; NC 1 located well before anterior margin of anterior nostril; NC 2 located level with anterior margin [before anterior margin (occasionally) or behind posterior margin of posterior nostril]; LC 1 located in front of anterior margin of eye; LC 2 located postero-ventrally below LC 1 (10 of 82 specimens, Fig. 12E ) [antero-ventrally below LC 1 (44 of 82 specimens) to just below LC 1 (28 of 82 specimens, Fig. 12B ); PO 1 located just behind posterior margin of orbit; PO 2 on similar horizontal level as PO 1; PR 1 and PR 2 located on ventral surface and lateral to opercle, respectively; PR3 located postero-ventrally below PO 2 (18 of 79 specimens, Fig. 12E ) [antero-ventrally below PO 2 (16 of 79 specimens, Fig. 12B ) or just below PO 2 (45 of 79 specimens)]; all pores with membranous tube ( Fig. 12 ).

Coloration in life and fresh ( Figs. 6B , 10 ): Body brownish yellow to red. Ventral surface of head slightly whitish. Black stripe on snout tip through eye to posterior region of head (occasionally indistinct: Fig. 10G ). Dorsal, anal and caudal fins yellow to red, with margins whitish. Anterior part of dorsal fin occasionally with black smudge ( Fig. 10F, G ). Pectoral fin translucent. Disc whitish to yellowish.

Coloration when preserved: Uniformly yellowish or pale yellow.

Distribution. Endemic to East Asia ( Fig. 7 ). Known from Japan, and northern and eastern coasts of Taiwan and Vietnam, respectively. Examined Japanese specimens were collected from the Pacific coast of Kanagawa, Chiba and Shizuoka prefectures, Izu Islands (Miyake-jima island), Shikoku (Tokushima and Kochi prefectures), western coast of Kyushu (Nagasaki and Kagoshima prefectures), Osumi Islands (Tanega-shima and Yaku-shima islands), Tokara Islands (Suwanose-jima island), Amami Islands (Amami-oshima and Yoron-jima islands), Okinawa Islands (Okinawa-jima island), and Ogasawara Islands (Chichi-jima island). The species has also been recorded from the Sea of Japan [Shimane ( Briggs 1955) and Yamaguchi (based on an underwater photograph: Fig. 6B ) prefectures].

Remarks. Tanaka (1908) described Aspasma misakia on the basis of two specimens (5.4 and 3.3 cm) (deposited at ZUMT), from Misaki, Miura, Kanagawa, Japan The smaller specimen (ZUMT 1982, paratype) is now considered to have been lost, our search of the ZUMT collection having been unsuccessful. It should be noted that the catalogue number of the holotype, given as ZUMT 1781 by Tanaka (1908), was in error, the correct number being ZUMT 1981. According to the ZUMT ledger, ZUMT 1781 is a non-type specimen of the gobioid Odontobutis obscura ( Temminck & Schlegel 1845) . Although originally placed in Aspasma Jordan & Fowler 1902, the species clearly belongs to Lepadichthys , having the following combination of characters: pelvic disc single; 3 of 5 gill arches with filaments [3 gills (sensu Briggs 1955)]; gill membranes on each side united ventrally and attached to isthmus; snout comparatively short and broad, its length 8.5–12.6 (mean 10.6) % of SL; disc length 16.3–20.8 (18.5) % of SL; upper-jaw teeth thickened, the tips strongly curved posteriorly; lower-jaw teeth with pointed conical tips; and premaxillae separated anteriorly by large circular gap in dorsal view ( Briggs 1955).

Briggs (1955) regarded A. misakia as a junior synonym of L. frenatus . However, detailed comparisons of the holotype of A. misakia and a large number of additional Northern Hemisphere specimens with the type specimens of L. frenatus and non-type Southern Hemisphere specimens revealed specific differences between the two groups (see Discussion). Accordingly, A. misakia (= L. misakius ) is reinstalled here as a valid species.

Motomura et al. (2010) recorded L. misakius from Yaku-shima island, Kagoshima, southern Japan on the basis of 20 specimens. Subsequently, Motomura & Aizawa (2011) re-identified one of those specimens (KAUM–I. 11266) as Lepadichthys coccinotaenia Regan 1921 ( Motomura & Harazaki 2017). However, the specimen was reconfirmed here as L. misakius . In fact, L. coccinotaenia has not been positively confirmed as occurring in Japanese waters, other records of that species from Japan (e.g., Hayashi & Hayashi 1985) having been subsequently recognized simply as Lepadichthys sp. ( Hayashi & Hagiwara 2013).

Figures

FIGURE 3. Radiographs of caudal skeletons of Lepadichthys frenatus (A, B) and L. misakius (C, D). (A), AMS I 20268-026, 39.9 mm SL; (B), AMS I 20463-015, 43.1 mm SL; (C), KAUM–I. 56686, 41.5 mm SL; (D), CMNH-ZF 12210, 45.8 mm SL.

FIGURE 4. Pelvic discs of Lepadichthys frenatus (A–C) and L. misakius (D–F). (A), AMS IB. 6682; (B), AMS IB. 6164; (C), AMS I. 20256-013; (D), BSKU 103919; (E), CMNH-ZF 12460; (F), CMNH-ZF 12091. A–B (with straight lines) and bar indicate disc region (see text) and 1 mm, respectively.

FIGURE 6. Underwater photographs of Lepadichthys frenatus (A) (Lord Howe Island, New South Wales, Australia in 10 m depth: Photo by T. Davis) and L. misakius (B) (Omi-jima island, Yamaguchi, Japan: Photo by S. Inoue). Specimens not collected.

FIGURE 7. Distributional map of Lepadichthys frenatus (blue circles) and L. misakius (red triangles). (A), map of the western Pacific Ocean; (B), map of Japanese waters. Closed and open symbols indicate records based on specimens examined in this study and published literature or photographs, respectively. Arrowheads indicate type locality.

FIGURE 9. Preserved (A–C) specimen of Aspasma misakia, ZUMT 1981, holotype, 51.9 mm SL, Misaki, Miura, Kanagawa, Japan. (A), lateral view; (B), dorsal view; (C), ventral view; (D), x-radiograph.

FIGURE 10. Fresh specimens of Lepadichthys misakius. (A–C), KAUM–I. 79067, 27.2 mm SL, Amami-oshima island Kagoshima, Japan; (D), KAUM–I. 17522, 37.4 mm SL, Amami-oshima island Kagoshima, Japan; (E), KAUM–I. 40010, 22.6 mm SL, Yoron-jima island, Kagoshima, Japan; (F), KAUM–I. 41853, 42.0 mm SL, Yaku-shima island, Kagoshima, Japan; (G), CMNH-ZF 12210, 45.8 mm SL, Katsuura, Chiba, Japan. (A, D–G), lateral views; (B), dorsal view; (C), ventral view.

FIGURE 11. CT scanned skeleton of Lepadichthys misakius, CMNH-ZF 7652, 20.1 mm SL. (A–C), overall shape; (D–F), close up of head. (A, D), dorsal view; (B, E), lateral view; (C, F), ventral view.

FIGURE 12. Head sensory canal pores of Lepadichthys misakius. (A–C), CMNH-ZF 15415, 21.2 mm SL; (D–F), KAUM–I. 56686, 41.5 mm SL. (A, D), dorsal views; (B, E), lateral views; (C, F), ventral views. Abbreviations as in Fig. 5. Bar indicates 1 mm.