Roughjaw Frogfish

Roughjaw Frogfish, Fowlerichthys avalonis

The Roughjaw Frogfish, Fowlerichthys avalonis, whose common Spanish name is ranisapo antenado, is a species in the Frogfish or Antennariidae Family, known collectively as ranisapos in Mexico. Globally, there are only five species in the genus Fowlerichthys, three of which are found in Mexican waters, two in the Atlantic and one in the Pacific.

The Roughjaw Frogfish have globose, slightly compressed bodies with a large oblique mouth featuring numerous small villiform teeth. They are highly variable in color, being found in various shades of yellow, orange, red, brown, or black with pronounced light and dark mottling. They have large black spots surrounded by a narrow orange ring on the rear base of the dorsal fin. Their eyes are on the sides of their head. They have small gill openings found behind and below the pectoral fin base. Their first dorsal spine (the “illicium”) is large and free, forming a movable “fishing rod” that is approximately equal in length to the second dorsal spine. The enticement lure (the “esca”) is an oval shaped cluster of numerous short vertically aligned appendages that is about 40% of the pole length. The second dorsal spine is attached to the head by a membrane. The third dorsal spine is movable and not bound by skin. They have large pectoral fins that are elongated and “leg-like” with an “elbow” joint.

The Roughjaw Frogfish are a sedentary species found on flat sand or muddy bottoms from the intertidal zone at depths up to 1,000 feet. They reach a maximum length of 53 cm (20.9 inches); this length was established by a fish in my possession that is photographed below. They are voracious carnivores that sit quietly waiting for small fish to pass by. They also stalk fish and crustaceans. Reproduction occurs via pelagic eggs whereby a single female can release up to 300,000 eggs which form a buoyant “raft” that remains afloat for several days until hatching.

In Mexican waters the Roughjaw Frogfish are found in all waters of the Pacific.

The Roughjaw Frogfish can be confused with the Bandtail Frogfish, Antennatus strigatus (stand alone third dorsal spine with a large pointed hump; short fishing pole) and the Sanguine Frogfish, Antennatus sanguineus (belly with numerous brown spots).

The Roughjaw Frogfish is of limited value being used in the aquarium trade at modest level.

Roughjaw Frogfish, Fowlerichthys avalonis. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, May 2011. Length: 53 cm (21 inches) which establishes a new maximum length for this species by a full 17 cm (6.7 inches).

Roughjaw Frogfish, Fowlerichthys avalonis. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, June 2010. Length: 26 cm (10.2 inches).