Ateleopus japonicus Bleeker 1853

Kaga, Tatsuya, 2017, Redescription of Ateleopus japonicus Bleeker 1853, a senior synonym of Ateleopus natalensis Regan 1921 (Teleostei: Ateleopodiformes: Ateleopodidae), Zootaxa 4238 (4), pp. 583-592 : 584-586

Ateleopus japonicus Bleeker 1853

[Japanese name: Shachiburi] ( Figs. 1–4 ; Table 1)

Ateleopus japonicus Bleeker 1853: 19 (based on the description of Temminck & Schlegel 1846); Temminck & Schlegel 1846: 255, pl.112, fig. 1 (description, type locality: Entrance of the large bay in the Oomura district, Nagasaki [prefecture], Japan [= Sasebo Bay]); Sauter 1905: 234 (key); Howell Rivero 1935: 93 (description); Okada & Matsubara 1938: 62, pl. 9, fig. 3 (key); Matsubara 1955: 272, pl. 25, fig. 91 (key); Stauche & Blache 1964: 50 (description); Shen & Ting 1972: 24, fig. 5 (description); Mochizuki 1984: 115, pl. 100 (description); Kulbicki et al. 1994: 14 (checklist); Randall & Lim 2000: 591 (checklist); Mochizuki 2001: 109 (description); Shinohara et al. 2001: 298 (checklist); Aizawa 2002: 347 (key); Amaoka & Kobayashi 2003: 109, figs. 1–3 (description of postlarva); Shinohara et al. 2005: 407 (checklist); Bray & Hoese 2006: 457 (checklist); Shinohara et al. 2009: 700 (checklist); Fricke et al. 2011: 358 (checklist); Aizawa & Doiuchi 2013: 410 (key); Okiyama 2014: 269 (description of larva); Kaga et al. 2015: 391 , figs. 1–9 (description).

Ateleopus schlegelii van der Hoeven 1855: 326 (based on the description of Temminck & Schlegel 1846, type locality: Entrance of the large bay in the Oomura district, Nagasaki [prefecture], Japan [= Sasebo Bay]).

Ateleopus purpureus Tanaka 1915: 565 (type locality: Ibaraki, Japan); Tanaka 1916: 396, pl. 107, fig. 328 (description); Howell Rivero 1935: 96 (description); Okada & Matsubara 1938: 62, pl. 9, (key); Matsubara 1955: 273 (key); Okamura 1985: 439, fig. 218 (description); Xu 1988: 145, fig. 115 (description); Shinohara et al. 2001: 299 (checklist); Aizawa 2002: 347 (key); Shinohara et al. 2005: 407 (checklist); Prokofiev 2006: 342 (description); Shinohara et al. 2009: 701 (checklist); Aizawa & Doiuchi 2013: 410 (key).

Ateleopus tanabensis Tanaka 1918: 223 (type locality: Wakayama, Japan); Howell Rivero 1935: 96 (description); Okada & Matsubara 1938: 62 (key); Matsubara 1955: 273 (key); Randall & Lim 2000: 591 (checklist); Mochizuki 2001: 109 (description); Shinohara et al. 2001: 299 (checklist); Aizawa 2002: 347 (key); Kitagawa et al. 2008: 28 (description); Shinohara et al. 2009: 701 (checklist); Aizawa & Doiuchi 2013: 410 (key).

Ateleopus natalensis Regan 1921: 414 (type locality: off Umuoti River, 15 miles out, Natal, South Africa); Howell Rivero 1935: 96 (description); Barnard 1948: 350, fig. 3 (description); Stauche & Blache 1964: 50 (description); Smith 1965: 116, fig. 188 (description); Smith 1986: 405, fig. 124.2 (description); Goren & Dor 1994: 17 (checklist); Manilo & Bogorodsky 2003: S97 (checklist); Golani & Bogorodsky 2010: 14 (checklist).

Lectotype. RMNH 1410 (800 mm SL; Fig. 2 A), Entrance of the large bay in the Oomura district, Nagasaki (prefecture), Japan (= Sasebo Bay).

Other materials. 85 specimens (185–820 mm SL): ZUMT 8320 (holotype of Ateleopus tanabensis Tanaka 1918 , 345 mm SL), Tanabe , Wakayama, Japan ; ZUMT 8321–8323 (3 paratypes of A. tanabensis , 212–243 mm SL), Tanabe , Wakayama, Japan ; BMNH 1921.3.1.7–8 (2 syntypes of A. natalensis , 460–515 mm SL; Fig. 1 ), off Umuoti River , 15 miles out, Natal, South Africa ; BMNH 1939.5.24.573 (formerly as A. natalensis , 572.5 mm SL), Zanzibar area, Tanzania ; CAS 224559 (2, 363– 456 mm SL), Tashi , Yilan, northeastern Taiwan, bottom trawler ; CAS 235639 (298 mm SL), between Luzon Island and Mindoro Island, Philippines ; FKUN 11585, 21863–21865 , 21867, 22639– 22640 (7, 325– 638 mm SL), Owase , Mie, Japan, bottom trawler ; FKUN 32626 (227 mm SL), Kiinagashima , Mie, Japan, bottom trawler ; FKUN 33359–33363 (5, 316– 565 mm SL), Suruga Bay , Shizuoka, Japan ; HUMZ 35540– 35541 (2, 423– 427 mm SL), off Cape Ashizuri , Kochi, Japan ; HUMZ 49542 (440 mm SL), Tosa , Kochi, Japan, 180 m, bottom trawler Kousei Maru ; HUMZ 49815, 105809 , 109326 (3, 413– 427 mm SL), Mimase Fishmarket , Kochi, Japan ; HUMZ 52245 (543 mm SL), Miya Fishmarket , Gamagoori, Aichi, Japan ; HUMZ 72942, 106481 (2, 723– 764 mm SL), Fish Festival in Odawara, Kanagawa, Japan ; HUMZ 106766 (497 mm SL), Ida , Numazu, Shizuoka, Japan, 250 m ; HUMZ 185291, 185292 (2, 185– 258 mm SL), Hagi Bay , Yamaguchi, Japan, 10–20 m, mid-trawl ; HUMZ 185353 (252 mm SL), Owase , Mie, Japan, 400 m ; HUMZ 191786–191826 (41, 232– 820 mm SL), Kiinagashima , Mie, Japan, 150–300 m, bottom trawler ; HUMZ 192387 (236 mm SL), Mito , Ibaraki, Japan, 310 m, bottom trawler Wakataka Maru ; HUMZ 193074, 193075 (2, 395– 431 mm SL), fish market, Tashi , Taiwan ; SAIAB 13451 (formerly as A. natalensis , 3, 343– 363 mm SL), off Ras Ngomeni , Kenya ; SAIAB 48129 (formerly as A. natalensis , 444 mm SL), off Mozambique, Mozambique ; SU31358 (formerly as A. natalensis , 464 mm SL), KwaZulu-Natal, Natal, South Africa .

Diagnosis. A species of Ateleopus with 8–10 dorsal-fin rays, 1 1–14 pectoral-fin rays, 94–131 anal-fin+caudalfin rays, 0+8–11=8–11 gill rakers, 26–29+86–107=113–136 vertebrae, one to three rows of small teeth on upper jaw, a large obtuse spine projecting from posterior margin of eye, tip of pelvic fin enlarged and round, and tail long (range 70–83% of SL).

Description. Counts and measurements of Ateleopus japonicus , including the lectotype of A. japonicus and A. schlegelii , the holotype and paratypes of A. tanabensis , and the syntypes of A. natalensis are given in Table 1. For description of the lectotype of A. japonicus and A. schlegelii (a stuffed specimen) see Kaga et al. (2015).

Body elongate, compressed; tail long, tapering to caudal fin; body completely enveloped in soft gelatinous tissue, without scales except for thin scales embedded in lateral line. Head large, about five to ten times into SL, slightly compressed, covered with thick gelatinous tissue forming gelatinous snout in adults ( Fig. 2 B) but not in juveniles (up to ca. 250 mm SL). Anterior nostril with a short tube; posterior nostril large, without a tube, situated just in front of upper half of eye. Eye small, its diameter approximately equal to or slightly shorter than pectoral-fin base. Interorbital space wide, with a deep longitudinal groove. A large obtuse spine projecting from posterior margin of eye. Two small obtuse spines between large obtuse spine and gill opening. Mouth inferior, protractile, rather small. Posterior end of maxilla extending to, or a little beyond, center of eye. Both lips rough, densely covered with tiny tooth-like papillae.

Upper jaw with one row of villiform teeth in specimens to ca. 320 mm SL, usually developing into villiform tooth band in specimens larger than 320 mm SL, rarely one row; tooth band wider anteriorly; teeth in lower jaw small canines, deciduous, arranged in one row and situated anteriorly; the lower jaw teeth sometimes all fallen out.

Palatine, vomer, and tongue toothless. Symphysis of lower jaws convex in front. Preopercular margin not free; gill opening wide; gill membranes separate, free from isthmus. Posterior margin of opercle usually acute, rarely rounded on one side. Gill rakers on upper part of lower limb of first gill arch flattened, lower ones stumpy: rakers on other gill arches all stumpy. All tips of gill rakers bluntly pointed, the edge weakly spinulose. No pseudobranchiae. Branchiostegal rays usually seven. Dorsal-fin origin slightly behind base of pectoral fin. Dorsalfin base short, less than snout length. Dorsal fin long, its length approximately equal to pectoral-fin length. Pectoral fin long, the tip not reaching origin of anal fin until a size of ca. 280 mm SL attained; the tip reaching or extending beyond origin of anal fin in most of specimens from ca. 280 to ca. 385 mm SL, the tip not reaching origin of anal fin in specimens larger than ca. 385 mm SL. Pelvic fin jugular, consisting of four autogenous rays in postlarva of 185 mm SL; four long rays and a minute ray in postlarva 258 mm SL; anterior three long rays attached with cutaneous membrane enclosing posterior two rays, the third ray longest with swollen and slightly flattened tip in juvenile specimens ca. 227–270 mm SL; anterior two rays short or rudimentary attaching to base of third ray, with vestigial rays in the cutaneous membrane in specimens larger than 270 mm SL. Precise count of pelvic-fin rays difficult in adults because of cutaneous membrane and rudimentary anterior two rays becoming very small. Proportional length of pelvic-fin ray variable, regardless of growth size, extending to point anywhere between base of pectoral and proximity of anus. Anal-fin base long, continuous with caudal fin. Anal-fin pterygiophores visible through gelatinous tissue. Anus just in front of anal-fin origin.

Color when fresh. Blackish or dark purplish, translucent; all fins blackish except translucent first rays of dorsal and pectoral fins, and whitish tip of pelvic fin.

Color in preserved specimens. Brownish, blackish, grayish or translucent; all fins blackish or brownish except brownish or whitish first rays of dorsal and pectoral fins, and white tip of pelvic fin.

Distribution. Known from along coasts of Japan northward to southern Tohoku district, Okinawa Trough; East and South China Seas; north-western Western Australia and eastern Australia; Chesterfield Island in Coral Sea; the western Indian Ocean including the Arabian Sea, the Red Sea, and the region south of the Red Sea to the Cape of Good Hope. Depth range from 100 to 600 m, on sandy-muddy bottoms.

Figures

FIGURE 1. Syntypes of Ateleopus natalensis, BMNH 1921.3.1.7 – 8 (A; 460 mm SL and B; 515 mm SL). Photographed by James Maclaine.

FIGURE 2. Ateleopus japonicus (A; lectotype of A. japonicus and A. schlegelii, RMNH 1410, 800 mm SL, from Kaga et al. 2015) and (B; HUMZ 191815, 445 mm SL).

FIGURE 3. Relationships of A) length from snout tip to dorsal-fin origin, and B) length from lower-jaw tip to anus (% SL) versus standard length (SL) in syntypes of Ateleopus natalensis (solid squares), non-types of “ A. natalensis ” (empty squares), lectotype of A. japonicus and A. schlegelii (solid circle), non-types of A. japonicus (empty circles), holotype of A. tanabensis (solid triangle), paratypes of A. tanabensis (empty triangles). A. schlegelii and A. tanabensis has already been synonymized under A. japonicus by Kaga et al. (2015).

FIGURE 4. Relationships of A) snout length, B) longest dorsal-fin ray, and C) pectoral-fin length (% LTJA) to the length from lower-jaw tip to anus (LTJA) in syntypes of Ateleopus natalensis (solid squares), non-types of “ A. natalensis ” (empty squares), lectotype of A. japonicus and A. schlegelii (solid circle), non-types of A. japonicus (empty circles), holotype of A. tanabensis (solid triangle), paratypes of A. tanabensis (empty triangles). A. schlegelii and A. tanabensis has already been synonymized under A. japonicus.