Rainbow Basslet, Liopropoma fasciatum
The Rainbow Basslet, Liopropoma fasciatum, whose common Spanish name is cabrilla arcoiris, is a species in the Grouper or Epinephelidae Family, known collectively as serranos in Mexico. Globally, there are twenty-seven species in the genus Liopropoma, six of which are found in Mexican waters, four in the Atlantic and two in the Pacific.
The Rainbow Basslets have elongated bodies and pointed heads. They have a near horizontal profile with large eyes and a slightly upturned and very large mouth with a projecting lower jaw. Their head and belly are red and there are four horizontal stripes on their sides: a wide dark brown mid-lateral stripe, straddled by a strong yellow stripe above and a faint yellow stripe below, and a red-brown stripe just below the base of their dorsal fin (pictured below). Their dorsal fin has 7 rays and a yellow stripe near the base. They have a very deep tail base, which is greater than half the depth of the body, and their tail is concave. They are covered with small rough scales.
The Rainbow Basslets are found in and around rocky and coral reefs at depths between 75 and 750 feet. They reach a maximum of 33 cm (13 inches) length and 450 grams (1 pound) in weight. They are a rare deep water species, which lacks significant scientific behavioral information.
In Mexican waters the Rainbow Basslet have a limited distribution being only found in the lower two-thirds of the Sea of Cortez and along the coast of the mainland southward to Guatemala.
The Rainbow Basslet is straightforward to identify due to its unique coloration pattern. In body shape it is similar to the Scalyfin Basslet, Liopropoma longilepis, however, the latter lacks the mid-body banding.
The Rainbow Basslet is a rare catch by hook and line and is too small to be of interest to most. They are however, a very colorful fish and one of the few bright oceanic fishes; as a result, they are sold extensively by the aquarium trade.
Rainbow Basslet, Liopropoma fasciatum. Fish caught from coastal waters off Puerto Los Cabos, Baja California Sur, February 2007. Length: 18.0 cm (7.1 inches). Identification courtesy of Dr. Ross Robertson, Smithsonian Tropical Research Institute, Panama.
Rainbow Basslet, Liopropoma fasciatum. Fish caught from coastal waters off Point Palmilla,, Baja California Sur, March, 2016. Length: 16.5 cm (6.5 inches).