Corydoras panda the entire fin area. The caudal peduncle is marked with a black band, this black band encircling the caudal peduncle from dorsal to ventral surface. The adipose fin, supported by a small fin spine, sometimes contains black pigmentation. The head is the same ground colour as the body, with a black mask surrounding the eyes, descending vertically from the fontanel, over each eye, and ending in a triangular wedge immediately before the ventral surface of the head. The pectoral fins are positioned immediately behind the operculum, and are usually oriented horizontally when the fish is at rest, extended in a
Lanternfish pectoral fins, usually with eight rays, may be large and well-developed to small and degenerate, or completely absent in a few species. In some species, such as those of the genus "Lampanyctus", the pectorals are greatly elongated. Most lanternfish have a gas bladder, but it degenerates or fills with lipids during the maturation of a few species. The lateral line is uninterrupted. In all but one species, "Taaningichthys paurolychnus", a number of photophores (light-producing organs) are present; these are paired and concentrated in ventrolateral rows on the body and head. Some may also possess specialised photophores on the caudal peduncle,