Coffin Ray - Description

Description

The unusual pear-like shape of the coffin ray distinguishes it from all other rays. Its body is flabby, with the two large, kidney-shaped electric organs visible on both sides of the head. The pectoral fins form a greatly enlarged disc about as wide as long, that is thick at the center and thin at the margins. The leading margin of the disc is straight to gently concave. The eyes are minute and can be elevated on short stalks. Close behind the eyes and slightly larger are the spiracles, which are rimmed by small papillae in some individuals. The nostrils are located just ahead of the mouth, and are connected to it by a pair of broad grooves. Between the nostrils is a short curtain of skin that overlaps the mouth. The capacious mouth forms a very long, wide arch; the slender jaws can be distended dramatically, though are not particularly protrusible. Adults have over 60 rows of small teeth in either jaw; each tooth has three long cusps. The five pairs of gill slits are small and placed beneath the disc.

The pelvic fins are relatively large and merged with the pectoral fin disc at the front to form a roughly circular secondary disc. The two dorsal fins are shaped like rounded lobes and are located very close to the caudal fin, which is of similar size with a nearly symmetrical, rounded margin. The tail is extremely short, such as that the caudal fin barely extends past the pelvic fin disc. The skin is entirely devoid of dermal denticles, and may be creased in areas. The dorsal coloration ranges from dark to reddish brown, to grayish, pinkish, or yellowish, and may be plain or sparsely patterned with irregular darker and lighter markings. The underside is pale, as are the spiracle papillae. This species grows to a length of 70 cm (28 in), or possibly even 92 cm (36 in), though most are only around 40 cm (16 in) long.