The tubemouth whipray (Urogymnus lobistoma) is a little-known species of stingray in the family Dasyatidae, named for its distinctive, highly protrusible jaws.

It is found in shallow, brackish water near mangrove forests and large river mouths along the coasts of southwestern Borneo and southern Sumatra.

Measuring up to 1 m (3.3 ft) across, this species has a diamond-shaped pectoral fin disc with an elongated, pointed snout and broadly rounded outer corners.

The first known specimens of the tubemouth whipray were caught from the South China Sea in 1999, and initially thought to be Dasyatis microphthalmus, a species of dubious taxonomic validity.

As additional specimens emerged, this ray was described as a new species by B. Mabel Manjaji-Matsumoto and Peter Last in a 2006 issue of the scientific journal Ichthyological Research.

[4] The tubemouth whipray has only been found in the South China Sea off southern Sumatra and southwestern Borneo, to as far north as Bintulu.

However, its population has likely declined significantly over the past few decades due to extensive degradation of its mangrove habitat, and intense, unregulated coastal trawl and bottom longline fisheries that take it for meat.