Enneapterygius phoenicosoma Motomura, Ota, and Meguro, 2015

Motomura, Hiroyuki, Ota, Ryohei, Meguro, Masatoshi & Tashiro, Satokuni, 2015, Enneapterygius phoenicosoma, a New Species of Triplefin (Tripterygiidae) from the Western Pacific Ocean, Species Diversity 20 (1), pp. 1-12 : 2-10

Enneapterygius phoenicosoma Motomura, Ota, and Meguro , n. sp.

[New English name: Red-bodied Triplefin; new Japanese name: Aka-hebigimpo]

( Figs 1–6 , 8 A–B, 9; Tables 1 –3)

Enneapterygius sp. 1: Ogaya in Takagi et al. 2010: 115, unnumbered 5 figs (Morode, Ehime, Shikoku, Japan).

Enneapterygius sp. 2: Meguro in Motomura and Matsuura 2014: 457, unnumbered 2 figs (Yoron-jima island, Amami Islands, Kagoshima, Japan).

Enneapterygius sp.: Iwatsubo et al. 2014: 89, fig. 11 (off Bandokorobana Nature Park, Ei, Minami-kyushu, Kagoshima, Japan).

Holotype. KAUM–I. 21960, male, 35.1 mm SL, off Nagasaki-bana , Kushikino-kose, Ichiki-kushikino, Kagoshima, Japan, 31°42′24″N, 130°15′44″E, 0.5–1 m, 4 August 2009, T. Yoshida, G. Ogihara, and M. Yamashita.

Paratypes. 70 specimens, 17.2–37.2 mm SL, all from Japan. IZU PENINSULA: NSMT-P 62088 , female, 27.2 mm SL, off Ryugu-jima island , Shimoda, Shizuoka, 3–5 m, 20 December 2001, G . Shinohara and M . Yanagida . SHIKOKU: BSKU 75367 , male, 28.6 mm SL, BSKU 75368 , female, 30.0 mm SL, Murote Bay , Ainan, Ehime, 10 July 2005, E. Katayama; BSKU 101171 , male, 23.7 mm SL, south side of Murote Bay , Ainan, Ehime, 21 April 2005, T. Ogaya; BSKU 101172 , male, 22.8 mm SL, south side of Murote Bay , Ainan, Ehime, 18 May 2005, T. Ogaya ; BSKU 114638 , female, 26.3 mm SL, BSKU 114639 , male, 25.9 mm SL, off Tei Beach, Kounan, Kochi, 23 June 2007 . EASTERN KYUSHU (PACIFIC SIDE): KAUM–I. 6122, male, 33.0 mm SL, KAUM–I. 9623, male, 28.1 mm SL, KAUM–I. 9624, female, 27.8 mm SL, KAUM–I. 9629, female, 25.9 mm SL, KAUM–I. 9630, male, 27.1 mm SL, tidepool at Shirahama , Miyazaki, 31°79′N, 131°48′E, 0.1–0.5m, 26 April 2008, M. Meguro and H. Iwatsubo . WESTERN KYUSHU ( EAST CHINA SEA SIDE): KAUM–I . 4249, male, 29.8 mm SL, off Kurose Beach , Kasasa , Minami-satsuma, Kagoshima, 31°22′29″N, 130°10′09″E, 2 m, 28 May 2007, M . Ito; KAUM–I . 16206, male, 33.4 mm SL, KAUM–I. 16207, male, 32.9 mm SL, KAUM–I. 16208, male, 32.9 mm SL, KAUM–I. 16232, male, 27.6 mm SL, MNHN 2015–0122 , female, 33.5 mm SL, MNHN 2015–0123 , male, 29.2 mm SL, off Nagasaki-bana , Kushikino-kose, Ichiki-kushikino, Kagoshima, 31°42′24″N, 130°15′44″E, 0.5 m, 15 March 2009, M . Meguro and T . Yoshida; KAUM–I . 21990, male, 33.9 mm SL, KAUM–I. 21991, male, 32.8 mm SL, KAUM–I. 21994, male, 33.7 mm SL, KAUM–I. 25833, female, 34.5 mm SL, KAUM–I. 26185, male, 33.7 mm SL, KAUM–I. 26186, male, 33.8 mm SL, KAUM–I. 26187, male, 32.1 mm SL, KAUM–I. 26188, male, 36.1 mm SL, KAUM–I. 26189, male, 37.2 mm SL, KAUM–I. 26190, female, 33.9 mm SL, KAUM–I. 26191, female, 31.9 mm SL, KAUM–I. 26192, female, 35.0 mm SL, KAUM–I. 26206, male, 35.1 mm SL, KAUM–I. 26207, male, 28.6 mm SL, KAUM–I. 26208, male, 30.4 mm SL, KAUM–I. 26209, male, 29.6 mm SL, KAUM–I. 26210, male, 28.5 mm SL, KAUM–I. 26211, male, 27.2 mm SL, KAUM–I. 26250, male, 28.8 mm SL, KAUM–I. 26251, male, 27.5 mm SL, KAUM–I. 26252, female, 32.0 mm SL, KAUM–I. 26253, female, 32.0 mm SL, KAUM–I. 26254, female, 31.8 mm SL, KAUM–I. 26255, female, 31.3 mm SL, KAUM–I. 26256, female, 28.7 mm SL, same data as holotype; KAUM–I . 40970, female, 28.6 mm SL, KAUM–I. 40971, female, 35.3 mm SL, KAUM–I. 40972, male, 31.0 mm SL, KAUM–I. 40973, male, 31.7 mm SL, off Nagasaki-bana , Kushikino-kose , Ichiki-kushikino, Kagoshima, 31°42′24″N, 130°15′44″E, 0.1–0.5m, 1 August 2011, M . Meguro; KAUM–I . 45375, male, 26.4 mm SL, off Nagasaki-bana , Kushikino-kose , Ichiki-kushikino, Kagoshima, 31°42′24″N, 130°15′44″E, 0.1–0.5 m, 1 August 2011, M . Meguro et al .; KAUM–I. 47301, male, 33.5 mm SL, off Nagasaki-bana , Kushikino-kose , Ichiki-kushikino, Kagoshima, 31°42′24″N, 130°15′44″E, 0.1–0.5 m, 1 August 2011, H . Motomura et al . SOUTHERN KYUSHU: KAUM–I. 32119, male, 30.2 mm SL, tidepool at Marukihama beach, Kushi , Bonotsu , Minami-satsuma, Kagoshima, 31°17′22″N, 130°12′45″E, 0.5 m, 10 September 2010, H . Motomura et al .; KAUM–I. 38722, female, 27.4 mm SL, off fishing port at Kushi , Bonotsu , Minami-satsuma, Kagoshima, 31°18′37″N, 130°13′19″E, 2–25 m, 14 June 2011, A . Simons et al .; KAUM–I. 47259, male, 30.0 mm SL, east coast of Chiringa-jima island, Ibusuki , Kagoshima Bay, Kagoshima, 31°16′37″N, 130°40′20″E, 0.3–1 m, 25 May 2012, H . Motomura et al .; KAUM–I. 55381, male, 28.3 mm SL, KAUM–I. 55382, male, 31.1 mm SL, KAUM–I. 55383, female, 30.8 mm SL, KAUM–I. 55384, male, 34.1 mm SL, KAUM–I. 55385, male, 31.2 mm SL, off Bandokoro-bana National Park , Beppu , Ei , Minami-kyushu, Kagoshima, 31°14′N, 130°26′E, 0.3 m, 23 June 2013, H . Iwatsubo; KAUM–I . 56701, female, 30.3 mm SL, off Bandokoro-bana National Park , Beppu , Ei , Minami-kyushu, Kagoshima, 31°14′N, 130°25′E, 4 m, 29 September 2013, H . Iwatsubo . OSUMI ISLANDS: KAUM–I. 29443, male, 31.2 mm SL, south coast of Iou-jima island , Mishima, Kagoshima, 30°46′32″N, 130°16′43″E, 10–20 m, 25 May 2010, KAUM Fish Team; KAUM–I . 53997, male, 28.2 mm SL, off Harutahama , Ambo , east coast of Yaku-shima island, Kagoshima, 30°18′03″N, 130°39′18″E, 8–10 m, 10 April 2013, S . Tashiro; KAUM–I . 56567, male, 19.0 mm SL, off Urata , Kunigami , Nishinoomote , Tanegashima island, Kagoshima, 30°49′36″N, 131°02′11″E, 4–8 m, 19 September 2013, S . Tashiro et al . AMAMI ISLANDS: CMNH-ZF 11219 , male, 25.3 mm SL, Kurasaki , Tatsugo , Amami-oshima island, Kagoshima, 28°25′55″N, 129°37′57″E, 10 m, 1 July 2004, Y . Ikeda and M . Aizawa; KAUM–I . 17513, male, 26.2 mm SL, tidepool at Tsuchihama , Kasari , Amami-oshima island, Kagoshima, 28°24′34″N, 129°40′31″E, 0.5–1.0 m, 27 March 2009, M . Meguro and T . Yoshida; KAUM–I . 40407, male, 21.3 mm SL, KAUM–I. 40408, male, 18.9 mm SL, off Maehama , Yoron-jima island, Kagoshima, 27°01′13″N, 128°26′26″E, 2–10 m, 17 August 2011, M . Meguro and E . Katayama; KAUM–I . 51390, male, 22.4 mm SL, off Chabana, Yoron-jima island , Kagoshima, 27°03′40″N, 128°25′02″E, 8 m, 26 October 2012, KAUM Fish Team; KAUM–I . 55016, male, 17.2 mm SL, off Yoron Port, Yoron-jima island , Kagoshima, 27°03′40″N, 128°25′02″E, 8 m, 29 June 2013, T . Trnski et al .; NSMT-P 31249 , male, 23.6 mm SL, off Sakinome Beach , Amami-oshima island, Kagoshima, 28°11′N, 128°16′E, 2–3 m, 12 September 1989, M . Aizawa . OKINAWA ISLANDS: KAUM–I. 41905, male, 27.6 mm SL, off Nago , Okinawa-jima island, 26°30′N, 128°02′E, 24 March 2011, Y . Sakurai .

Non-type material examined. 5 specimens, 20.4– 25.3 mm SL. CAROLINE ISLANDS: NSMT-P 22918 , male and female, 20.4–22.0 mm SL, south coast of Eten Island , Chuuk Islands, 0.5 m, 6 July 1982, K . Matsuura . VANUATU: USNM 362385 , male and female, 22.1–23.1 mm SL, Fisheries Wharf, Santo Island , 15°31′30″S, 167°09′32″E, 5 m, 12 May 1997, J . Williams et al .; USNM 344010 , male, 25.3 mm SL, Port Narevin, Erromango , 18°44′25″S, 169°12′41″E, 5.5 m, 28 May 1996; J . Williams et al .

Diagnosis. A small- to medium-sized species of Enneapterygius with the following combination of characters: 11–13 (mode 12) second dorsal-fin spines; 8–10 (9) third dorsal-fin soft rays; 15–17 (16) pectoral-fin rays; 16–18 (17) anal-fin soft rays; 32–35 (33) scale rows in longitudinal series; 16–19 (17) pored lateral-line scales; 16–19 (18) notched lateral-line scales; 1 scale row between last pored lateral-line scale and first notched lateral-line scale; mandibular pore formula 4–6+1+4–6 (4+1+4); long dorsal-fin spines and rays [e.g., lengths of second spine 8.6–12.6% of SL (mean 10.1%) and third spine 7.2–9.8% of SL (8.5%) in first dorsal fin; first spine 12.8–17.2% of SL (15.2%), second spine 13.8–18.2% of SL (15.9%), and third spine 14.2–18.4% of SL (15.8%) in second dorsal fin; and first soft ray 14.8–19.5% of SL (17.3%), second soft ray 14.7–18.9% of SL (16.9%), and third soft ray 13.9–19.1% of SL (15.9%) in third dorsal fin]; short second dorsal-fin base [25.0–32.9% of SL (mean 29.2%)]; short anal-fin base [36.9–43.5% of SL (mean 40.5%)]; nasal tentacle unbranched, flat, broadened distally ( Fig. 8A, B ); lower two-thirds of head, including lower half of eye, snout, lips, cheek, and opercle, and pectoral-fin base, dense black in nuptial males; upper head and body reddishbrown in males and females, reddish in nuptial males, with H-shaped and/or upside-down Y-shaped oblique brown bars on lateral surface of body in both sexes; caudal-fin base with vertical brownish band, its width subequal to pupil diameter, and narrow vertical white band behind brownish band in both sexes; narrow, indistinct, white line along posterior margin of black area on pectoral-fin base in nuptial males; pectoral, pelvic, and anal fins reddish in nuptial males; no fins black.

Description. In following text, data for the holotype are presented first, followed by paratype data (if different) in parentheses. Counts and measurements of the holotype, paratypes, and non-types are given in Tables 1 –3. The cephalic sensory pore systems of the holotype are illustrated in Fig. 5 A–C; major variation of sensory pores on the occipital region is shown in Fig. 5D .

Dorsal fin III, XII, 9 (III, XI–XIII, 8–10); anal fin I, 17 (I, 16–18); 16 (15–17) pectoral-fin rays; 34 (32–35) scale rows in longitudinal series; 17 (16–19) pored lateral-line scales; 17 and 18 (16–19) notched lateral-line scales; 4 (3 or 4) scale rows above first pored lateral-line scale; 3½ and 4 (2½–4) scale rows between first spine base of second dorsal fin and pored lateral-line scale; 3½ (2½–4) scale rows below first notched lateral-line scale; 2½ and 3 (2–3) scale rows above last pored lateral-line scale; 12 (11 or 12) circumpeduncular scales; 4+1+4 (4–6+1+4–6) mandibular pores.

Body moderately elongate, slightly compressed anteriorly, progressively more compressed posteriorly; dorsal profile of snout not strongly steep. Mouth slightly oblique; posterior margin of maxilla extending slightly beyond vertical drawn through anterior margin of pupil; anterior tip of upper jaw almost reaching as high as ventral margin of orbit. Anterior nostril membranous tube with thin, but distally broadened, unbranched tentacle ( Fig. 8A, B ); anterior nostril located at level of middle of eye, slightly closer to eye than to upper lip; posterior nostril opening elliptical. Eye oriented dorsolaterally; simple tentacle on posterodorsal margin of eye, its length subequal to length of nostril tentacle. Interorbital space narrow, its width narrower than pupil diameter. Opercular margin extending beyond vertical drawn through base of third spine of first dorsal fin.

Lateral line discontinuous, with anterior series of pored scales and posterior series of notched scales; pored scale series ending below membrane between last spine of second dorsal fin and body; notched scale series beginning below last pored scale (or below third or second scale from last pored scale or below a point just posterior to last pored scale) and ending at caudal-fin base; one scale row between posteriormost pored scale and anteriormost notched scale; one additional notched scale present (or scale absent) anterior to 2 (1–4) normal scales followed by series of notched scales. Body scales ctenoid; no scales on head, including maxilla, interorbital space, preopercle, and opercle, pectoral-fin base, pre- and inter-pelvic-fin region, or pre-dorsalfin region; no scales on fin membranes except for basal part of caudal fin.

Origin of first dorsal fin at vertical drawn between preopercular and opercular margins; first spine of this fin longest, third spine shortest. Origin of second dorsal fin above fifth (third to fifth) pored lateral-line scale, second (rarely third) spine of this fin longest. Origin of third dorsal fin above 20th (19th to 21st) longitudinal scale; second (or first) ray of this fin longest. Origin of pelvic fin anterior to vertical drawn through base of first spine of first dorsal fin, below posterior edge of preopercle. Base of uppermost pectoral-fin ray below second pored lateral-line scale. Pectoral fin pointing posteriorly, with posterior tip of its longest ray not reaching vertical drawn through origin of third dorsal fin (usually just reaching vertical drawn through base of last spine of second dorsal fin). Origin of anal fin below sixth (fifth to seventh) spine base of second dorsal fin.

Color of nuptial male specimens when fresh —Based on color photographs of holotype ( Fig. 1A ) and 22 paratypes ( Fig. 2 ): lower two-thirds of head, including lower half of eye, snout, lips, cheek, and opercle, and pectoral-fin base, dense black (dark grey with scattered large gray blotches); remaining part of head and body reddish with 11 (9–12) H-shaped and/or upside-down Y-shaped oblique brown bars on lateral surface of body. Narrow, indistinct, white line along posterior margin of black area on pectoral-fin base. Caudal-fin base with vertical brownish band, its width subequal to pupil diameter, and narrow vertical white band behind brownish band. First dorsal fin semi-transparent, yellowish (or reddish) basally and distally; spines reddish. Second dorsal fin semi-transparent with melanophores scattered on basal one-third of fin, forming broad, pale gray band; distal margin of fin grayish. Third dorsal fin semitransparent without distinct bands or stripes. Pectoral fin semi-transparent with red rays. Pelvic fin rays red (or pink). Anal fin red with reddish (or whitish) rays. Caudal fin semitransparent with whitish or reddish rays and without distinct bands or stripes, with reddish ventral margin.

. holotype of count Includes

1

Color in life of nuptial males —Based on several underwater photographs (see Fig. 4 ): similar to the above, but narrow white line along posterior margin of black area on pectoral-fin base more distinct.

Color in life of pale males and females —Based on several underwater photographs (see Figs 2–3 ): head mottled with brown, white, blue, and green blotches, spots, and lines. Body whitish with 9–12 H-shaped and/or upside-down Yshaped oblique brown bars on lateral surface of body; caudal-fin base with vertical brownish band and narrow vertical white band behind brownish band. First dorsal fin whitish. Second dorsal fin semi-transparent with pale gray band basally. Third dorsal, anal, and caudal fins semi-transparent. Pectoral fin semi-transparent; narrow white line along posterior margin of pectoral-fin base. Color of female specimens when fresh ( Fig. 3 ) similar to their color in life.

Color in preservative of nuptial males —Lower two-thirds of head, including lower half of eye, snout, lips, cheek, and opercle, and pectoral-fin base black; remaining part of head and body whitish with oblique grayish bars on lateral surface of body. Caudal-fin base with vertical grayish band. Second dorsal fin semi-transparent, grayish basally. Third dorsal, pectoral, anal, and caudal fins semi-transparent with white rays. Pelvic-fin rays white.

Color in preservative of females —Similar to coloration of preserved male specimens, but head and pectoral-fin base pale and mottled with scattered melanophores.

Distribution and ecological notes. Currently known from the western Pacific Ocean: Japan, the Caroline Islands, and Vanuatu. In Japanese waters, E. phoenicosoma has been recorded from the Pacific coast of southern Japan, including the Izu Peninsula, Shikoku, and southern Kyushu, and the Ryukyu Islands. This species usually occurs in open tide-pools and areas with strong regular surges generated by wave swells. Individuals usually inhabit the surface of large rocks, but also slits and holes in large rocks, at depths of less than 25 m (usually less than 15 m). Spawning of E. phoenicosoma at Shikoku occurs from early morning until about 10 am starting in June (Ogaya in Takagi et al. 2010; reported as Enneapterygius sp. 1).

Etymology. From the Greek “ phoenico ” meaning red and “ soma ” body, in reference to the red body of nuptial males. The name is used as a noun in apposition.

Remarks. The nuptial coloration of males of E. phoenicosoma n. sp., including their black head and pectoralfin base and reddish body, is distinct from the coloration of females; however, detailed analyses of 32 morphometric features (listed in Table 1 ) revealed no other sexual dimorphism.

Most specimens of the new species were collected from shallow waters in southern Japan, where it is relatively common . We also found a few specimens from the Caroline Islands and Vanuatu, which we have tentatively identified as belonging to this species . More specimens are required to fully assess the taxonomic status of these specimens from the central western Pacific Ocean , so they are excluded from the type series of E . phoenicosoma.

Figures

Fig. 1. Holotype of Enneapterygius phoenicosoma n. sp. (KAUM–I. 21960, male, 35.1mm SL, Ichiki-kushikino, Kagoshima, Japan). A, fresh specimen; B, preserved specimen.

Fig. 2. Males of Enneapterygius phoenicosoma n. sp. from Ichiki-kushikino, Kagoshima, Japan. A, KAUM–I. 40972, paratype, 31.0mm SL; B, KAUM–I. 40973, paratype, 31.7mm SL. In each case, the preserved specimen and the underwater photograph represent the same individual. Underwater photographs taken at depths of 0.1–0.5m show the normal coloration of males, and the coloration changes to the nuptial coloration immediately after death.

Fig. 3. Female of Enneapterygius phoenicosoma n. sp. KAUM–I. 40970, paratype, 28.6mm SL, Ichiki-kushikino, Kagoshima, Japan. The two photographs represent the same individual.

Fig. 4. Underwater photographs of nuptial males and females of Enneapterygius phoenicosoma n. sp. A, nuptial male, off Nobeoka, Miyazaki Prefecture, east coast of Kyushu, Japan, 0–2m depth, 5 August 2007 (photo by K. Ota); B, nuptial male, off east coast of Izu Peninsula, Japan, 6–10 m depth (photo by S. Yamamoto); C, nuptial male, off Kii Peninsula, Japan, 11–15 m depth, 12 October 2008 (photo by D. Itou); D, nuptial male and two females, off Otsuki, Kochi Prefecture, Shikoku, Japan, 5m depth, 29 October 2014 (photo by K. Matsuno). Live nuptial males have a reddish body with a black head and pectoral-fin base, a distinct white band along the posterior margin of the black area on the pectoral-fin base, and no dense black fins.

Fig. 5. Cephalic sensory pore system of Enneapterygius phoenicosoma n. sp. Dorsal (A), lateral (B), and ventral (C) views of head of holotype (KAUM–I. 21960, male, 35.1mm SL, Ichiki-kushikino, Kagoshima, Japan); dorsal view (D) of head of paratype (KAUM–I. 26186, male, 33.8mm SL, Ichiki-kushikino, Kagoshima, Japan). Nostrils and tentacles not illustrated; scale bar 2mm.

Fig. 6. Distributional records of Enneapterygius phoenicosoma n. sp. and E. atriceps. Stars, localities of specimens of E. phoenicosoma; closed circles, localities of specimens of E. atriceps examined in this study; open circles, localities of specimens of E. atriceps examined by Fricke (1997).

Fig. 8. Tentacle on anterior nostril. A–B, holotype (KAUM–I. 21960, 35.1mm SL) of Enneapterygius phoenicosoma n. sp.; C–D, non-type (ANSP 28022, 18.6mm SL) of E. atriceps. Upper (A, C) and lower (B, D) represent lateral and posterior views respectively. Scale bars 0.1mm.