They do not have pelvic fins and there are no scales on their body but in one species the body is covered in papillae. There are 19-25 spines and 7-17 soft rays in the dorsal fin and 5-11 spines and 3-7 soft rays in the anal fin.
They do not possess pelvic fins or scales but one species is covered with papillae. The dorsal fin contains 19-25 spines and 7-17 soft rays, while the anal fin has 5-11 spines and 3-7 soft rays.