Tete Sea Catfish, Ariopsis seemanni
The Tete Sea Catfish, Ariopsis seemanni, whose common Spanish name is bagre tete, is a member of the Sea Catfish or Ariidae Family, known collectively as bagres marinos in Mexico. Globally, there are 22 species in the genus Ariopsis, of which three are found in Mexican waters, one in the Atlantic and two in the Pacific.
The Tete Sea Catfish have elongated and easily recognizable “catfish” bodies. They are iridescent silver dorsally and transition to white ventrally. Their fins are dusky with the exception of the pelvic fins, which are black with a white border. Their head is dominated by large protruding eyes. They have three sets of barbels that are used to probe the bottom for food. Their adipose fin is two-third the length of the dorsal base; their anal fin has 17 to 20 rays; their caudal fin is deeply forked; their dorsal fin has one spine and seven rays and contains a toxin venom; and their pectoral fins have one strongly serrated spine and 10 or 11 rays. They have wide gill openings with 5 to 8 gill rakers on the first arch and 9 to 15 gill rakers on the second arch. Their lateral line is complete. They have no scales and their skin is smooth to the touch.
The Tete Sea Catfish are a demersal species found in a variety of habitats; they are common in small schools in coastal marine and brackish waters at depths up to 75 feet and are found in and around river mouths at elevations up to 100 feet. They reach a maximum length of 35 cm (14 inches) with females being larger than males. They have an acute sense of smell and are opportunistic feeders being active carnivorous scavengers and consuming benthic crustaceans and insect larvae. In turn they are preyed upon by a variety of sharks and bottlenose dolphins. In brackish environments they are also preyed upon by water snakes. Reproduction is oviparous with annual cycles. Following spawning and fertilization in the ocean, eggs are mouthbrooded by males and transported to freshwater environments where the fry are released. At maturity the small fish return to oceanic environments. They have the ability to produce sound, which is used as a defense mechanism, in courtship, and for spawning. They have a lifespan of up to 15 years.
In Mexican waters the Tete Sea Catfish have a limited distribution being found within La Paz Bay and along the west coast of the mainland from Guaymas south to Guatemala.
The Tete Sea Catfish can be easily confused with the Cominate Sea Catfish, Occidentarius platypogon (long and thin dorsal fin; uniformly colored pelvic fins) and the Widehead Sea Catfish, Ariopsis guatemalensis (small eyes; strong and serrated pectoral spine).
The Tete Sea Catfish are used in the aquarium trade at a modest level and have been given such attractive names as the Colombian Shark Catfish and the White Tip Shark Catfish. Juveniles are very attractive but will expire without high maintenance. They are difficult to maintain, requiring large water volumes, brackish waters for juveniles, higher saline content as they mature, and strongly oxygenated water with good flow. They also prey on smaller tank mates. They are not suitable for home aquariums. They are sold commercially as a food fish and marketed fresh or salted and have been retained by subsistence fishermen for centuries. They are unregulated throughout their range. They are prone to mass mortality during cold water episodes. They are believed to play an important role in coastal ecosystems. From a conservation perspective, they are considered of Least Concern, being widespread and common in many locations.
Tete Sea Catfish, Ariopsis seemanni. Fish caught in coastal waters off Mazatlán, Sinaloa, October 2017. Length 31 cm (12 inches). Catch, photo, and identification courtesy of Josh Leisen (lifelistfishing.com), Gaylord, MI.