Spotfin Cusk-eel, Ophidion galeoides
The Spotfin Cusk-eel, Ophidion galeoides, whose common Spanish name is congriperla adornada, is a species in the Cusk Eel or Ophidiidae Family, known collectively as brotula and congriperlass in Mexico. Globally, there are twenty-seven species in the genus Ophidion, seven of which are found in Mexican waters, two in the Atlantic and five in the Pacific.
The Spotfin Cusk-eels have robust elongated compressed bodies that taper towards the rear. They have a silvery brown coloration that is lighter ventrally. They have a dark spot just above their pectoral fin base after which they are named. Their flanks have a broken brown stripe along the lateral line with two or three spots below. Their anal fin has a broad black margin; their dorsal fin has a dark blotch at the front and a dark margin; and their pectoral fins have black tips. Their head has gill covers with a strong skin-covered spine at the upper corner. Their anal and dorsal fin bases are long and continuous with a rounded caudal fin. Their pectoral and pelvic fins are of equal length. Their pelvic fins each having two thread-like rays inserted under the eyes. Their head is devoid of scales, however, their body is covered with small, smooth, and elongated scales.
The Spotfin Cusk-eels inhabit sandy and muddy bottoms and are found demersal at depths up to 240 feet. They reach a maximum length of 22.0 cm (8.6 inches). They are rarely seen by humans because they hide in caves during the daytime and only emerge at night to feed on crustaceans, polychaete worms, small clams, and other invertebrates.
In Mexican waters the Spotfin Cusk-eels are found in all waters of the Pacific with the exception that they are absent from Magdalena Bay northward along the central and northwest coasts Baja, however, there is a known an isolated population residing in the Guerrero Negro area.
The Spotfin Cusk-eel is very similar to a series of other Cusk-eels and specifically the Leopard Cusk-eel, Lepophidium pardale, the Mimic Cusk-eel, Ophidion imitator, the Panamic Cusk-eel, Otophidium indefatigabile, and the Spotted Cusk-eel, Chilara taylori, however they all have bodies covered with various sizes and shapes of black spots and lines.
The Spotfin Cusk-eels are a by-catch of deep water trawlers, but are too rare and too small to be of commercial interest. They are of limited interest to most.
Spotfin Cusk-eel, Ophidion galeoides. Fish provided by the commercial fishermen of Bahía Kino, Sonora, November 2014. Length: 20 cm (7.9 inches). Photo courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.