Sanguine Frogfish, Abantennarius sanguineus

Sanguine Frogfish, Abantennarius sanguineus. Fish provided in a regurgitated format from a monster from the deep caught in coastal waters of the greater Los Cabos area, Baja California Sur, May 2018. Length: 6.6 cm (2.6 inches). Photograph courtesy of Eric Brictson, Gordo Banks Pangas, La Playita, Baja California Sur.

Sanguine Frogfish, Abantennarius sanguineus. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, September 2011. Length: 8.3 cm (3.25 inches).

The Sanguine Frogfish, Abantennarius sanguineus, is a member of the Frogfish or Antennariidae Family, that is also known as the Bloody Frogfish and is known in Mexico as ranisapo sangrón. This is one of the more exotic and most unusual fishes in the world and the most common Frogfish in the Tropical Eastern Pacific Ocean. Globally, there are three species in the genus Abantennarius, of which only this is species is found in Mexican waters of the Pacific Ocean.

The Sanguine Frogfish has a globose, slightly compressed body with a large oblique mouth featuring numerous small villiform teeth. They are highly variable in color, being found in various shades of yellowish brown to red with brown spotting and mottling. They have conspicuous brown spots on their belly. Some have a weak ocellus round spot below the rear of their 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 elongated tapering appendage with slender filaments and a cluster of darkly pigmented round swellings at the base. The second dorsal spine is also free; it is strongly curved and not 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 and their pelvic fins are short. Their body is covered with rough skin.

The Sanguine Frogfish is a sedentary species found over rocky bottoms from the intertidal zone at depths up to 40 m (130 feet). They reach a maximum of 13 cm (5.1 inches) in length. 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. The Sanguine Frogfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

In Mexican waters the Sanguine Frogfish is a resident of all waters of the Pacific with the exception that that they are absent from the entire the west coast of Baja and the northern 20% of the Sea of Cortez. The collection photographed above documents a 40-mile northerly range extension into the Pacific along the extreme southwestern coast of Baja.

The Sanguine Frogfish is an easy fish to identify and cannot be confused with any other species due to the brown spots on its belly which are not present on any other frogfish.

From a conservation perspective the Sanguine Frogfish has not been formally evaluated. They are of limited interest to most with the exception that they are utilized by the aquarium trade at modest level.