Threadfin Goosefish

Threadfin Goosefish, Lophiodes spilurus

Threadfin Goosefish, Lophiodes spilurus. Fish provided by the commercial fishermen of Bahía Kino, Sonora, November 2014. Length: 8.0 cm (3.1 inches). Photograph courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.

The Threadfin Goosefish, Lophiodes spilurus, is a member of the Goosefish or Lophiidae Family, and is known in Mexico as rape de hebra. Globally, there are fifteen species in the genus Lophiodes, of which three are found in Mexican waters, one in the Atlantic and two in the Pacific Ocean.

The Threadfin Goosefish has a body that is wide at the front and that flatten and taper towards the back. They have a uniform dark brown coloration and their fins have clear edges. Their caudal fin has a row of small clear spots; their second and third dorsal spines are black; and their gut cavity is black. Their head is covered with bony prickles and features a large wide mouth bearing long and sharp teeth. Their eyes are on top of the head, their top jaw is protractile, and their lower jaw is projecting. They have large gill openings that extend from behind to in front of their pectoral fin base. Their anal fin has 6 or 7 rays; their first dorsal fin has 3 standalone spines followed by 3 attached spines with the first dorsal spine, located at the tip of their snout just above the mouth, has been modified into an angling apparatus (illicium) that bears a bulb-like lure (esca) used to attract prey; their second fin  has 7 or 8 rays; their pectoral fins are somewhat unique being long and “arm-like” bony structures with 15 to 18 rays. Their body and fins are covered with tiny ciiri. They have smooth skin and are devoid of scales.

The Threadfin Goosefish is found over and within sandy and muddy bottoms at depths between 73 m (240 feet) and 457 m (1,500 feet). They reach a maximum of 35 cm (14 inches) in lenght. They are “lie in wait” ambush predators, feeding on small fish and crustaceans. The Threadfin Goosefish 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.

The Threadfin Goosefish is a resident of all Mexican waters of the Pacific Ocean with the exception that they are absent from the extreme northern portions of the Sea of Cortez.

The Threadfin Goosefish is very similar to, and can easily be confused with, the Spottedtail Goosefish, Lophiodes caulinaris (prominent row of white spots across caudal fin).

From a conservation perspective the Threadfin Goosefish is currently considered to be of Least Concern with stable, widely distributed populations. They are a rarely seen by humans and of interest to most. They are caught at a modest level by deep water trawlers and are a “catch-and-release.” I have provide a couple of these to one of the major countries within the European Community in 2012 and they used my fish to establish as a protocol for the DNA.  The DNA profile for the goosefishes included a total of seven global Goosefish that will be implemented to assist in the apprehension of fraudulent bad guys who are replacing “valuable fish high-cost fish with trash fish” and reaping big profits (Lorenze Castigliego, et al., Food Chemistry, 166, 1-9 (2015).  Or, who knows, they might become (ho ho) the next Patagonia Toothfish aka Chilean Seabass.