Sardinella pacifica, Hata, Harutaka & Motomura, Hiroyuki, 2019

Hata, Harutaka & Motomura, Hiroyuki, 2019, A new species of sardine, Sardinellapacifica from the Philippines (Teleostei, Clupeiformes, Clupeidae), ZooKeys 829, pp. 75-83 : 75

Sardinella pacifica sp. n. Figures 1, 2, Table 1

Sardinella fimbriata : Fowler 1941: 609 (Bacon, Manilla and Aparri, Philippines); Chan 1965 (in part): 14 (Philippines); Rau and Rau 1980: 203 (Philippines); Whitehead 1985 (in part): 98, unnumbered fig. (Philippines); Conlu 1986: 45, fig. 20 (Alabat Island; Appari, Cagayan; Bacon, Sorsogon; Bauang, La Union; Calapan, Mindoro; Cavite, Cavite; Davao Gulf; Estancia, Iloilo; Malolos, Bulacan; Manila Bay; Margosatubig, Zamboanga; Nasugbu, Batangas; Ragay Gulf, Quezon; San Miguel Bay, Camarines Sur; Samar, Philippines); Munroe et al. 1999 (in part): 1814, unnumbered fig. (Philippines); Luceño et al. 2013: 30, fig.2 (Butuan, Dipolog, and Pagadian, Mindanao Island, Philippines); Stern et al. 2016 (in part): 9, fig. 2 (b), fig. 4 (b) (Manilla, Philippines). (non Valenciennes)

Holotype.

BMNH 1985.4.12.1, 105.1 mm SL, Manila Harbor, Manila Bay, Luzon Island, Philippines.

Paratypes.

20 specimens, 90.2-105.9 mm SL, all from the Philippines. BMNH 1960.4.7.52, 90.2 mm SL, Palawan Island; BMNH 1985.4.12.2, 98.7 mm SL, Manila Harbor, Manila Bay, Luzon Island; CAS 38365, 105.9 mm SL, Manila Bay, Luzon Island; CAS 51909, 96.5 mm SL, Manila Bay, Luzon Island; CAS 52501, 98.4 mm SL, Manila Bay, Luzon Island; CAS 59712, 100.3 mm SL, Bacon, Sorsogon, Luzon Island; CAS-SU 28568, 96.5 mm SL, Alabat Island; CAS-SU 28569, 101.3 mm SL, Manila Bay, Luzon Island; CAS-SU 29920, 2 specimens, 97.6-103.3 mm SL, Manilla Bay, Luzon Island; CAS-SU 32915, 2 specimens, 95.7-97.8 mm SL, Manila Bay, Luzon Island; KAUM–I. 125000, 95.9 mm SL, Manila Bay, Luzon Island; USNM 56232, 94.5 mm SL, USNM 56233, 92.2 mm SL, Bacon, Sorsogon, Luzon Island; USNM 72197, 92.9 mm SL, Manila, Luzon Island; USNM 177667, 2 specimens, 93.4-96.7 mm SL; USNM 403460, 95.9 mm SL, Navatos, Manila, Luzon Island; USNM 427789, 94.9 mm SL, Catbalogan, Samar Island, Visayas.

Diagnosis.

A species of Sardinella with the following combination of characters: caudal fin with black posterior margin; lateral body scales with centrally discontinuous vertical striae, and few perforations and pores posteriorly; 38-41 (modally 38) lateral scales in longitudinal series; body scales deciduous; black spot on dorsal-fin origin; pelvic fin with one unbranched and seven branched rays; gill rakers 40-53 (43) in upper series on 1st gill arch, 71-84 (72) in lower series, 112-137 (118) in total; gill rakers 40-56 (42) in upper series on 2nd gill arch, 70-94 (79) in lower series, 112-148 (115) in total; gill rakers 37-52 (42) in upper series on 3rd gill arch, 57-75 (60) in lower series, 95-127 (99) in total; gill rakers 31-43 (35) in upper series on 4th gill arch, 44-63 (48) in lower, 78-106 (80) in total; gill rakers 30-43 (34) on hind face of 3rd gill arch; 17 or 18 (18) + 12 or 13 (13) = 29-31 (30) scutes on ventral edge of body; anal fin with 18-21 (20) rays; lower jaw rather short, 10.4-11.6% of SL.

Description.

Counts and measurements, expressed as percentages of SL, are given in Table 1. Data for the holotype are presented first, followed by paratype data in parentheses. Body oblong, compressed, deepest at dorsal-fin origin. Dorsal profile of body elevated from snout tip to dorsal-fin origin, thereafter decreasing to uppermost point of caudal-fin base. Ventral profile of body curved downward from lower-jaw tip to pelvic-fin insertion, thereafter rounded to ventralmost point of caudal-fin base. Abdomen from isthmus to anus with 30 (29-31) scutes. Predorsal scutes absent. Anteriormost point of pectoral-fin insertion anterior to posteriormost point of opercle. Upper, posterior and ventral margins of pectoral fin nearly linear. Posterior tip of pectoral fin pointed. Pectoral-fin axillary scale present. Posteriormost dorsal-fin ray not filamentous. Anteriormost point of pelvic-fin insertion located directly below origin of 8th (7 th– 10th) dorsal-fin ray. Posterior tip of depressed pelvic fin reaching between a vertical through posterior end of dorsal-fin base and anus. Pelvic-fin axillary scale present. Anal-fin origin posterior to vertical through posteriormost point of dorsal-fin base. Two posteriormost anal-fin rays enlarged. Caudal fin forked. Posterior tips of caudal-fin lobes pointed. Anus on ventral midline, slightly anterior to anal-fin origin, posterior to midpoint of body. Scales cycloid, thin, deciduous, except for robust ventral scutes. Scales on lateral body surface with several centrally discontinuous vertical striae, few perforations and pores posteriorly (Fig. 2). Bases of dorsal and anal fins with low scaly sheaths. Predorsal scales paired. No elongate, wing-like scales present beneath normal paired scales. No scales on head and fins, except for a broad triangular sheath of scales on caudal fin. Mouth terminal, small, posterior tip of maxilla not reaching vertical through anterior margin of iris. Premaxilla and hypomaxilla without teeth. Ventral margin of maxilla toothed. Lower jaw with several conical teeth anteriorly. Posterior ramus of lower jaw elevated. Second supramaxilla symmetrical. Orbit elliptical, eye and iris round. Eyes covered with adipose eyelid posteriorly. Interorbital space flat. Nostrils close to each other, anterior to orbit. Eight (8-10) on top of head. No lateral line. Gill rakers long, slender, with small asperities on anterior surface. Pseudobranchial filaments present. Gill opening with two fleshy outgrowths on posterior margin and a large papilla on ventral margin. Posterior margins of preopercle and opercle smooth.

Color of preserved specimens.

Body dark brown dorsally, elsewhere yellowish silver. Black spot on dorsal-fin origin. Melanophores scattered on upper part of dorsal fin and first pectoral-fin ray. Posterior margin of caudal fin dark. Fresh coloration shown in Luceño et al. (2013) (as S. fimbriata ).

Distribution.

Currently known only from the Philippines.

Etymology.

The specific name pacifica (in reference to the Pacific Ocean) is given to distinguish the species from S. fimbriata , with which it had been confused, and which is now considered to be restricted to the Indian Ocean.

Remarks.

The new species is assignable to the genus Sardinella , defined by Whitehead (1985) and Munroe et al. (1999), due to its compressed body, abdomen covered with prominently keeled scutes, paired predorsal scales, a symmetrical second supramaxilla, toothless hypo-maxilla, two posteriormost anal-fin rays enlarged, the dorsal fin without filamentous rays, and two fleshy outgrowths on the hind margin of the gill opening. It most closely resembles Sardinella fimbriata (Valenciennes, 1847) (Fig. 3), sharing centrally discontinuous striae on the lateral body scales, a dark spot on the dorsal-fin origin, more than 70 lower gill rakers on the first gill arch, eight pelvic-fin rays, 15-18 branched anal-fin rays, and 17 or 18 prepelvic scutes ( Whitehead 1985, Munroe et al. 1999, Stern et al. 2016). However, S. pacifica can be distinguished from the latter by lower counts of lateral scales in the longitudinal series (38-41 vs. 44-46 in S. fimbriata ; Table 1), pseudobranchial filaments (14-19 vs. 19-22; Table 1; Fig. 4A) and postpelvic scutes (12 or 13 vs. 13 or 14; Table 1), and a shorter lower jaw (10.4-11.6% SL vs. 11.1-12.2%; Table 1; Fig. 4B). Moreover, the deciduous body scales of the new species are distinctively diagnostic, the body scales of S. fimbriata being non-deciduous. Although S. fimbriata has been regarded as an Indo-West Pacific species, distributed from India to the Philippines ( Whitehead 1985, Munroe et al. 1999, Stern et al. 2016), no Pacific region specimens of S. fimbriata appear to have been collected (see comparative materials), and the species is judged herein to be an Indian Ocean endemic.

Comparative material examined.

Sardinella fimbriata (Valenciennes, 1847) (17 specimens, 89.7-123.6 mm SL): BMNH 1889.2.1.1778, 112.0 mm SL, Madras, India; BMNH 1889.2.1.1915-1916, 1 of 2 specimens, 97.9 mm SL, Orissa, India; BMNH 1889.2.1.1917, 99.5 mm SL, Akyab, Burma; CAS 41433, 2 specimens, 89.7-93.9 mm SL, Calicut, India; CAS 41434, 2 specimens, 94.2-97.2 mm SL, Ernakulam, Cochin, India; CAS 41435, 119.3 mm SL, Madras, India; MNHN 3227, lectotype of Spratella fimbriata , 118.2 mm SL, Malabar, India; USNM 276446, 121.8 mm SL, Cochin, Kerala, India; USNM 276447, 105.6 mm SL, Kovalam, Trivandrum, India; USNM 276449, 2 specimens, 108.7-114.6 mm SL, Vizhinam, Trivandrum, Kerala, India; USNM 276450, 4 specimens, 111.4-123.6 mm SL, Calicut, Kerala, India.