Cypselurus angusticeps folletti, Shakhovskoy & Parin, 2024

Shakhovskoy, Ilia B. & Parin, Nikolay V., 2024, A review of the flying fish genus Cypselurus (Beloniformes: Exocoetidae). Part 3. Revision of the subgenus Cypselurus sensu stricto with descriptions of one new species and four new subspecies and reinstatement of Cypselurus crockeri Seale and Exocoetus socotranus Steindachner, Zootaxa 5473 (1), pp. 1-125 : 95-97

Cypselurus angusticeps folletti subsp. nov.

Synonymy and bibliography.

Cypselurus angusticeps . Parin 1961a: 46 (in part: only specimens from Revillagigedo Is.).? Parin et al. 1990: 206 (listed; eastern Pacific, 4°S 89°W). Parin 1995: 1093, 1099, fig. 9b (distribution, diagnostic characters; eastern Pacific). Parin 1996: 302, 306 [359, 363] (distribution; in part: eastern Pacific). Castro-Aguirre & Balart 2002: 165 (listed; Revillagigedo). Lewallen et al. 2011: 164, figs. 2–3, 5 (molecular systematics). Fourriére et al. 2016: 456 (listed; Revillagigedo). Lewallen et al. 2018: 1758 (listed; eastern Pacific). Love et al. 2021: 93 (listed; off Todos Santos, 23°24.6’N 110°13.8’W).

Material examined. Fifty five specimens 76–225 mm SL.

Eastern Pacific Ocean. Full morphological study. IORAS 04438 (1, 225 mm SL), Socorro I., 3- 5.05.1925 . IORAS 04439 (paratype) (1, 200.5 mm SL), same data . IORAS 04440 (holotype, 210 mm SL), Socorro I., Braithwaite Bay , 26.03.1932 . LACM 30009-7 (1, 76 mm SL), 250–300 miles SW of Acapulco. LACM 30092-2 (1, 122 mm SL), Bajacalifornia, 200 miles SW Pta. San Telmo , 1st week May 1968 . LACM 31780-42 (1, 191 mm SL), Colima, Socorro I., 13- 14.02.1942 . LACM W52-177 - 1 (1, 202.5 mm SL), Revillagigedo Is., San Benedicto I., July 1952 . LACM W55-127 - 1 (2, 191– 198 mm SL), Socorro Id., off Binners Cove, 16.04.1955 . LACM W55-136 - 1 (1, 198.5 mm SL), Clarion I., SE end of Island, 20.04.1955 . LACM W56-140 - 1 (1, 158 mm SL), 16°05’N 102°55’W, 2.04.1956 . LACM W59-84 - 1 (1, 197.5 mm SL), 18°52’N 110°57’W, 13.05.1958 . SIO 57-165 (11, 197.5– 211 mm SL), 18°20’N 114°44’W, 19.04.1955 . SIO 58-144 (2, 196– 197 mm SL), Socorro Id, Braithwaite Bay . SIO 64-679 (1, 223.5 mm SL), Revillagigedo Is., 2–3 mi S of Socorro I., 2.08.1962 . SIO 64-695 (1, 215 mm SL), Revillagigedo Is., 1 mi S of Socorro I., 3.08.1962 . SIO 64-722 FB 62-248 (1, 190 mm SL), Socorro I., 2.08.1962 . SIO H46-770 (1538-46) (3, 193.5– 216 mm SL), Socorro I., 25.08.1946 . USNM 153428 (2, 192– 208.5 mm SL), Socorro I., 30.05.1949 .

Partial morphological study. LACM 38506-1 * (2, 185– 190 mm SL), Revillagigedos Is., San Benedicto I., 10.06.1979 . LACM W53-51 * (2,196– 210 mm SL), Socorro I . LACM W55-122 *(4,195– 212 mm SL), Revillagigedos Is . LACM W55-128 * (4, 194– 217 mm SL), Roca Partida . LACM W55-162 * (1, 221 mm SL), Clarion I . SIO 58-141 (9, 192– 205 mm SL), Socorro Id. Braithwaite Bay, 20.06.1954 .

Holotype ( Figs. 43c , 44c,f ). IORAS 04440 , Braithwaite Bay, Socorro I., Revillagigedo Is., 26 March 1932. Length 210 mm SL (male). D 13, A 9, P I 13, Spred 27, Str 7½, Sp.br 22 (6 + 16), Vert 41 (28 + 13). Measurements (in % SL): aA 77.8, aD 70.5, aV 59.0, cV 34.2, pV 37.6, c 24.6, po 11.0, o 7.3, ao 5.4, io 8.6, Hc 17.5, H 18.6, h 7.0, Dc 27.1, lP 65.2, lP1 40.9, lV 25.7, lD 19.4, lA 10.2, HD 10.0, HA 6.2, p 13.9. Body dark dorsally, silvery with golden shine ventrally. Pectoral fins gray to 9th ray with a small pale tip and very narrow pale posterior edging. Tip of pectoral fin protruding slightly beyond end of dorsal-fin base. Pelvic fins pale, reaching middle of anal-fin base. Dorsal fin gray, slightly darker in the upper part; tip of its last ray protruding beyond middle of caudal peduncle but not reaching origin of caudal-fin upper lobe. Anal fin grayish with few dark dots on anterior rays distally, its first ray beneath 6th dorsal-fin ray. Longest dorsal- and anal-fin ray—2nd. Caudal fin pale brown. Lower jaw shorter than upper jaw. Jaw teeth very small (not visible to the naked eye); three types of teeth are present: tricuspid, with additional cusps and conical. Palatine teeth absent.

Paratypes. IORAS 04439 , 200.5 mm SL, Socorro I., 3- 5.05.1925 . LACM 38506-1 , 185 and 190 mm SL, Revillagigedos Is., San Benedicto I., 10.06.1979 .

Differential diagnosis. Cypselurus a. folletti differs from C. a. angusticeps in more predorsal and transverse scales (Spred usually ≥ 27, Str usually ≥ 8 vs. Spred usually ≤ 27, Str usually ≤ 7½, see Tables 2–3), shorter head and smaller eye ( Fig. 40a–c ); juveniles elongated and leaner with a shorter and thinner chin barbel ( Figs. 40d–f , 43 ).

Etymology. The subspecies is named in honour of the late Dr. W.I. Follett (CAS), who gifted three specimens (among them the holotype and a paratype) to N.V. Parin when he visited California during 29th Cruise of R/V Vityaz in 1959.

Common name. The name “narrowhead flying fish” is mostly used for C. angusticeps . The name “eastern narrowhead flying fish” is proposed here for C. a. folletti.

Distribution. The subspecies is distributed ( Fig. 42 ) from off Isla Guadalupe (LACM 30092-2) south to about 14°N 103°W (LACM 30009-7). Love et al. (2021) listed C. angusticeps (folletti) for the waters off Todos Santos.

Parin et al. (1990) reported C. angusticeps south of Galapagos Islands (4°S 89°W), but in subsequent works ( Parin 1995, 1996), he did not reproduce this occurrence. Also, Grove et al. (2020: 20) listed this species as vagrant for Galapagos Archipelago (however, not providing any data on specimens and localities). Therefore, presence of C. angusticeps folletti in the waters of Galapagos needs confirmation.

Figures

FIGURE 40. Size variation of morphometric characters (in % SL) in Cypselurus angusticeps angusticeps (blue square— Polynesia, orange square—Hawaii, black square—western Pacific Ocean, lilac triangle—eastern Indian Ocean, green triangle— western Indian Ocean) and C. a. folletti (●). (A)—head length (c); (B) –postorbital distance (po); (C)—eye diameter (o); (D)—head depth (Hc); (E)—body width (p); (F)—length of chin barbel (Lcir).

FIGURE 42. Distribution of Cypselurus angusticeps angusticeps (○) and C. a. folletti (◊). Filled symbols indicate capture location for fishes ≤ 100 mm SL, open symbols indicate capture location for fishes> 100 mm SL; holotype position marked with asterisk.

FIGURE 43. Cypselurus angusticeps folletti subsp. n. (A)—76 mm SL, LACM 30009-7, 250–300 miles SW of Acapulco; (B)—122 mm SL, LACM 30092-2, 200 miles SW Pta. San Telmo; (C)—210 mm SL, IORAS 04440 (holotype), Braithwaite Bay; (D)—same as (A), close up of chin barbel.

FIGURE 44. Pectoral (A–C) and pelvic (D–F) fins of Cypselurus angusticeps folletti subsp. n. (A)—76 mm SL, LACM 30009- 7, 250–300 miles SW of Acapulco; (B)—202.5 mm SL, LACM W52-177-1, San Benedicto I.; (C & F)—210 mm SL, IORAS 04440 (holotype), Braithwaite Bay; (D)—158 mm SL, LACM W-56-140-1, 16°05’N 102°55’W; (E)—191 mm SL, LACM 31780-42, Socorro I.