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MUTANT STINGRAY OR ODD NEW SPECIES? Roger Steene, fish photographer and CoralRealm.com advisor, sent this photo of an odd stingray captured near the Great Barrier Reef. The specimen was taken in a shrimp trawl and according to the fishermen that captured the fish, it's not an "entirely uncommon" catch. I am not aware of how large this specimen is, but I will get this information from Roger and pass it on.

From the photo you can see that the pectoral fins are relatively short and kite-like. This specimen has two pairs of pelvic fins, and appears to have at least one set of claspers on the rearmost pair of pelvics. There are also three odd spines (two on one side, one on the other) behind the wing-like pectoral fins. My best guess is that these are cartilaginous processes, known as metapterygium, that extend from the pectoral girdle. The tail is also bent along its length in two locations. The well-developed ventral finfold indicates that this is probably a mutant cowtail stingray (Pastinachus sephen).

This species is wide-spread in the Indo-Pacific and attains a large size (adults can be as much as 1.8 m [5.9 feet] across the disc). It is found in a variety of habitats including estuaries and even well up rivers in freshwater. Why this species might produce some malformed offspring is not known.