Last photophore of VAL series behind origin of anal and last photophore of VAV series. Aggregation of luminous tissue on head, when fully developed fish > 10 cm SL, forming transverse bar across gill cover; longitudinally oriented aggregations of luminous tubercle-like spots on body behind head and above pelvic fins. In immature fish < 6 cm SL, chin barbel fully developed, longer than head, its swollen tip forming elongate thickened rod with two flattened distal lobes (Ref. 27676).