Shadowkiller got back to me with the ID of this whipray - he said this is a reticulate whipray (Himantura uarnak), not a leopard whipray (Himantura undulata) as mentioned in my previous post. According to him, a juvenile reticulate whipray has three rows of spots before its sting; this agrees with the description in Sharks and Rays of Australia (PR Last & JD Stevens, CSIRO Australia, 1994).
Based on the information about these two whipray species that I have gathered so far:
- The reticulate whipray is common in the waters of northern Australia between Shark Bay (Western Australia) and Brisbane (Queensland); the leopard whipray between Ningaloo (Western Australia) and Torres Strait (Queensland). So it's likely to find both species in Ningaloo.
- Juveniles of both species have dark spots on their bodies, but they can be distinguished based on the following features:
- (1) The tail of a juvenile reticulate whipray usually has three distinct rows of spots before the sting. Also, it has more than five (usually seven) spots in a direct line between the spiracles.
- (2) The tail of a juvenile leopard whipray usually has one row of spots on each side before the sting. Also, it has two or three spots between the spiracles.
Based on this photo, it is not easy to determine the number of spots between the ray's spiracles. But they certainly look like more than two or three.