A large eastern Pacific stingray on sand and rubble between the rock, with a whip tail much longer than the disc.
Disc to about 158 cm across. Total length reaches 2.57 m, but most of that is tail, so the disc width is the useful figure. The disc is diamond-shaped with angular corners and is about a sixth wider than it is long. Reddish-brown to dark grey above and pale below, with a row of pointed tubercles down the middle of the back. The tail is much longer than the disc and carries a serrated venomous spine.
The diamond stingray overlaps throughout the range and looks almost identical from above. The tail folds separate them: the diamond stingray has a fold above and below, this species has only the lower one. The name in older books is Dasyatis longa.
It is solitary, rests buried or half-buried in sand and mud, often where sand meets reef, and cruises slowly over open bottom hunting fish, mantis shrimp, crabs and molluscs. Divers meet it between about 5 and 30 m; it has been recorded to 90 m. At Revillagigedo it has been logged at Cabo Pearce on Socorro and at Las Cuevitas on San Benedicto.
The spine is a real hazard. On an animal this size the tail is long enough to reach well forward, the wound is severely painful and it infects readily. Do not approach a buried ray from above or behind, do not corner one against a wall, and shuffle rather than step in sandy shallows. It is listed as vulnerable.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.