Astronesthes richardsoni chin is ribbon-like and lacks a bulb or swelling at its tip. The dorsal fin has 12 to 14 soft rays and the anal fin has 13 to 18. The origin of the dorsal fin is behind the insertion of the pelvic fins. There is a dorsal adipose fin anterior to the caudal peduncle, and a small ventral adipose fin just anterior to the anus. There are two rows of photophores (luminous spots) on each side of the underside of the fish, numerous other photophores on the head and body and a luminous patch on the edge of the preoperculum;
Cerebral peduncle cerebral peduncles results in unrefined motor skills, imbalance, and lack of proprioception. The descending upper fibers from the internal capsule continue on through the midbrain and are then seen as the fibers in the cerebral peduncles. The cortico-pontine fibers are found in the outer and inner third of the cerebral peduncle, these are the cortical input to the pontine nuclei. The cortico-bulbar and cortico-spinal fibers are found in the middle third of the cerebral peduncle. The cortico-spinal tract exits the internal capsule and is seen in the mid portion of the cerebral peduncles. Cranial nerve 3 (oculomotor nerve) appears ventrally