Aetobatus ocellatus (Kuhl in Kuhl and van Hasselt, 1823 )

Aetobatus ocellatus (Kuhl in Kuhl and van Hasselt, 1823) View in CoL

IUCN standard name :: Spotted Eagle Ray Fig. 18 View Figure 18 , Table 2 View Table 2

Material examined.

UPVMI 3115, 574 mm DW, female, fish landing site, Sibunag, Guimaras Province, Philippines, 15 October 2020, coll. J. Fernandez.

Morphological description.

Body large; dorsal surface smooth; denticles and thorn absent from middle area; disc rhomboidal and broad, rather wide than long. Eyes moderately small and rounded; spiracles very large, located behind eye rather than below, and completely visible from dorsal view. Snout soft, large, protruding with blunt tip. Mouth moderately large. Nostrils large, partially covered by nasal flap; nasal flap moderately large, V-shaped, with posterior tips reaching lower jaw. Teeth plate on upper jaw rather wide than long in comparison to teeth plate on lower jaw; teeth on lower jaw elongated, extending beyond jaw, making it exposed when mouth is closed. Dorsal fin small, subtriangular with rounded apex. Pectoral fin very large, triangular with rounded apex, originating behind eye; anterior margin concave basally, becoming straight towards middle area, then convex towards rear; posterior margins concave in front, becoming straight towards rear; anterior edge entire or smooth and thick; posterior edge crenate and thin. Pelvic fin moderately elongated with rounded and crenate posterior margin. Tail tapering, very long, whip-like; dorsal and ventral folds absent; two spines positioned just behind dorsal fin; first spine was already removed upon purchase; second spine long, tapering with sharp, serrated margins. Gill slits located on underside short, with five on each side.

Color of fresh specimen. Dorsal area gray to black covered with small white spots; ventral area white with black fin edges; spots mostly concentrated on the pectoral and pelvic fins; few similar spots on the nape area; tail black.

Color of preserved specimen. Dorsal area dark brown; ventral area pale white; white spots still visible; tail black.

Distribution.

Tropical and warm temperate seas of the Indo-West Pacific. Red Sea, South Africa, Pakistan, India, Sri Lanka, Hawaii, Japan, Philippines, and Australia ( Last et al. 2010; de Carvalho and Soares 2022; this study).

DNA barcode.

The COI sequence of 617 bp was submitted to GenBank under accession number OR 614475.

Conservation status.

Vulnerable.

Remarks.

Aetobatus ocellatus can grow to a disc width of 3000 mm ( White et al. 2010) and is often found at depths of 20–25 m ( Randall and Cea 2011). Aetobatus ocellatus was categorized as “ uncertain (?) ” ( Alava et al. 2014; Santos et al. 2017); however, the presently reported study confirms its occurrence in the country (see Table 3 View Table 3 ). The distribution of this species within Philippine waters should be verified, as previous reports on Aetobatus narinari ( Euphrasen, 1790) from the Philippines may have referred to A. ocellatus .

The presently reported specimen was identified as A. ocellatus based primarily on its dark green to black dorsal surface, and the white spots, which were more restricted to the dorsal disc surface and did not extend to the head or eye regions. This identification was supported by molecular evidence (Fig. 12 View Figure 12 ). On the other hand, color photographs provided by White et al. (2010), show that the white spots on the dorsal surface of A. narinari are evenly distributed throughout the eye, head, and disc areas.

White et al. (2010) identified the major distinction between A. ocellatus and A. narinari as the background coloration on dorsal surface: A. ocellatus exhibit dark greenish, grayish, or nearly blackish color, sometimes with a pinkish tinge, whereas A. narinari is much paler yellowish-brown. Moreover, these two species show minor morphometric differences: A. ocellatus has a mean total length (measured from snout tip to tip of tail) of 281 % DW and a mean tail length (from anteriormost edge of the cloaca to the tail tip) of 230 % DW, whereas A. narinari measures a total length of 263 % and a tail length of 208 % DW. The Philippine specimen, with a total length of 271 % and a tail length of 219 % DW, is closer to A. ocellatus (4 % difference) in total length, compared to A. narinari (3 %). Both species show a similar 5 % difference in tail length relative to the Philippine specimen. Therefore, based on its dark green to black dorsal coloration, COI data, and total length, the Philippine specimen aligns more closely with A. ocellatus .