Bathytoma lacertosus is a species of sea snail, a marine gastropod mollusk in the family Borsoniidae.

The ribs are low, trabecular, and projecting in an acute angle from the shoulder.

Other lamellae continue as fine growth lines across the shell.

The spirals are faint threads, evanescent on the shoulder and prominent on the snout.

[3] This species occurs in the demersal zone of Southwest Pacific Ocean off Queensland and New South Wales, Australia.