Encrasicholina intermedia, Hata & Motomura, 2016

Hata, Harutaka & Motomura, Hiroyuki, 2016, Two new species of the genus Encrasicholina (Clupeiformes: Engraulidae): E. intermedia from the western Indian Ocean and E. gloria from the Persian Gulf, Red Sea and Mediterranean, Raffles Bulletin of Zoology 64, pp. 79-88 : 79-80

Encrasicholina intermedia , new species

[New English name: shiner anchovy] ( Figs. 1 , 3–5 ; Tables 1, 2)

Material examined. Holotype: RMNH. PISC 26135 , 57.7 mm SL, Kalient , Kerala, India, 16 August 1966 . Paratypes: 14 specimens, 49.8–75.2 mm SL. BMNH 1919.9 .12.6, 71.6 mm SL, Durban, South Africa, H. Marley; BMNH 1966.11.17.130–134 , 5 specimens, 68.2–75.2 mm SL, Mafia Channel, Tanzania, 07°42’N, 39°37’E, ca. 34.7 m, December 1965, G. Losse; BMNH 1968.4 .4.38, 50.5 mm SL, Formosa Bay, Kenya, 23 November 1965, G. Losse; KAUM–I. 80905, 49.9 mm SL, RMNH. PISC 38393 , 2 , 49.9 –57.0 mm SL, Kalient, Kerala, India, 16 August 1966, Kerala State Fish Office; MNHN 1969-0057 , 2 , 54.1–55.3 mm SL, Kalient , Kerala, India, 08°30’00”N, 76°49’59”E, I. Ronquillo; USNM 204229 , 2 , 54.8 –56.0 mm SL, Kalient , Kerala, India, 16 August 1966 .

Diagnosis. A species of Encrasicholina with the following combination of characters: dorsal and anal fins with two unbranched rays; pseudobranchial filaments 21–26 (modally 24); gill rakers 20–23 (20) in upper series on 1st gill arch, 26–28 (26) in lower series, 46–50 (46) in total; gill rakers 13–14 (13) in upper series on 2nd gill arch, 23–25 (23) in lower series, 36–38 (36) in total; gill rakers 10–12 (11) in upper series on 3rd gill arch, 12–13 (13) in lower series, 23–25 (24) in total; gill rakers 9–10 (10) in upper series on 4th gill arch, 9–11 (10) in lower, 19–21 (20) in total; prepelvic scutes 3–6 (5); posterior tip of upper jaw not reaching to anterior margin of preopercle; length of first unbranched dorsal-fin ray 4.7–5.8% of SL.

Description. Data for the holotype are presented first, followed by paratype data in parentheses. Body cylindrical, elongate; greatest body depth at dorsal-fin origin. Dorsal profile of head and body slightly convex from snout tip to dorsal-fin origin, straight along dorsal-fin base. Ventral profile of head and body slightly convex from lower-jaw tip to pelvic-fin insertion, slightly convex to straight from pelvic-fin origin to anal-fin origin, almost straight along anal-fin base. Dorsal and ventral profiles of caudal peduncle slightly concave. Belly slightly rounded, covered by 4 (3 to 6) sharp needle-like scutes anterior to insertion of pelvic fins. Postpelvic and predorsal scutes absent. Anus situated just anterior to anal-fin origin. Caudal peduncle compressed, its depth greater than eye diameter. Head large, compressed. Snout length less than eye diameter, tip rounded. Interorbital width less than orbit diameter. Mouth large, inferior, ventral to body axis, extending backward beyond posterior margin of eye. Lower jaw slender, longer than upper jaw, 108.7% (100.4–119.1%) of upper-jaw length, 62.9% (59.0–67.0%) of head length. Posterior tip of maxilla blunt, scarcely projecting beyond second supra-maxilla, not reaching to anterior border of preopercle. Single rows of conical teeth on jaws and palatines. Small conical teeth on vomer. Eye large, round, covered with adipose eyelid, lateral on head, dorsal to horizontal through pectoral-fin insertion, visible in dorsal and ventral views; pupil round. Orbit elliptical. Nostrils close to each other, positioned anterior to anterior margin of orbit and above horizontal through midline of body. Posterior margin of preopercle smooth. Subopercle with rounded posterior margin. Opercular membrane without serrations. Interorbital space flat. Pseudobranchial filaments present, length of longest filament less than eye diameter. Posterior frontal fontanelles on top of head near occiput open. Gill rakers long, slender, rough, visible from side of head when mouth open. Distance between pectoral-fin and pelvic-fin insertions slightly shorter (or slightly longer in some paratypes) than distance between pelvic-fin insertion and anal-fin origin. Isthmus muscle short, not reaching anteriorly to posterior border of gill membrane, preceded by exposed urohyal between gill membranes. Exposed urohyal with two small fleshy lobes laterally. Gill membrane not broadly joined over isthmus. Scales thin, cycloid, deciduous, except for prepelvic scutes. Scales absent on head. Lateral line absent. Scales absent on fins except for broad triangular sheath of scales on caudal fin. Pectoral-fin axillary scale missing (present in some paratypes). Dorsal-fin origin posterior to vertical through base of last pelvic-fin ray, positioned approximately at mid body. Dorsal-fin base short, its length 83.1% (76.7–95.2%) of anal-fin base length. Dorsal and anal fins with two anteriormost rays unbranched. First dorsal-fin ray and first anal-fin ray rather shorter. Two anteriormost dorsal-fin and anal-fin rays closely spaced. Anal-fin origin posterior to vertical through base of last dorsal-fin ray; posterior tip of depressed anal fin falling short of caudalfin base. Caudal fin forked. Uppermost pectoral-fin ray unbranched, inserted below horizontal through midline of body; posterior tip of pectoral fin falling short of pelvic-fin origin; 2nd (1st or 2nd) ray longest. Pelvic fin shorter than pectoral fin, insertion anterior to vertical at dorsal-fin origin. Posterior tip of depressed pelvic fin not reaching to anus, reaching vertical through base of 5th (3rd–6th) dorsal-fin ray.

Colour of preserved specimens. Head and body almost uniformly pale brown, with a faint silver-gray, longitudinal band, its width slightly broader than pupil diameter, from just posterior to upper opercular margin to caudal-fin base. Black melanophores scattered on occipital, upper part of opercle, and silver longitudinal band.

Distribution. Currently known only from the southeast coast of Africa (Durban, South Africa; Mafia Channel, Tanzania; and Formosa Bay, Kenya) and the southwest coast of India (Kerala State) ( Fig. 5 ).

Etymology. The specific name intermedia , an adjective from the Latin, refers to this species having the intermediate number of gill rakers between those of E. punctifer and E. gloria .

Figures

Fig. 1. Holotype of Encrasicholina intermedia, new species. RMNH.PISC 26135, 57.7 mm SL, Kalient, Kerala, India.

Fig. 3. Frequency distribution of number of total gill rakers of Encrasicholina intermedia, new species, E. gloria, new species, and E. punctifer; stars indicate data for holotypes.

Fig. 4. Relationships of 1st unbranched dorsal-fin ray length to standard length in Encrasicholina intermedia, new species [closed squares (open square = holotype)], E. gloria, new species [closed triangles (open triangle = holotype)], and E. punctifer (closed circles).

Fig. 5. Distributional records of Encrasicholina intermedia, new species (squares), E. gloria, new species (triangles), and E. punctifer (circles), based on specimens examined in this study.