Indo-Pacific: Maldives and Mauritius to the Society Islands, north to the Ryukyu Islands, south to the Great Barrier Reef.

Preopercular serrae 30-58. H. cuniculus is variable in coloration, ranging from pale olive brown to yellowish or light greenish or a mixture with some geographic variation.

Inhabits muddy to rubble or rubble-sand areas of outer reef slopes. Observed a meter above the substrate and retreats to a burrow when threatened. Stomach contents consist of calanoid copepods (58% by volume), larvaceans (20%), siphonophores (20%), and fish eggs (2%) (Ref. 8991). Sometimes in loose groups.