Splitnose Searobin

Splitnose Searobin, Bellator xenisma

The Splitnose Searobin, Bellator xenisma, whose common Spanish name is vaca doble hocico, is a species in the Searobin or Triglidae Family, known collectively as rubios and vacas in Mexico. Globally, there are only eight species in the genus Bellator, six of which are found in Mexican waters, three in the Atlantic and three in the Pacific.

The Splitnose Searobins have rectangular block-like bodies that are mottled reddish brown in color with white undersides. Their large square bony head is covered with many ridges and spines. Their anal fin has a wide dark red marginal band, their caudal fin is black with a central white bar and a dark spot on the lower lobe, and their pelvic fins are transparent. They have a prominent ocellus spot between the fourth and fifth dorsal spines. Their pectoral fins are dark. Their mouth is small and their jaw does not reach eye level. Their snout has a pair of prolonged snout plates that form a “scalloped” shovel-shaped extension on each side of the snout tip. They have two separated dorsal fins with 10 or 11 spines and 10 or 11 rays with the first spine being the longest (a key to identification). Their pectoral fins are short, but reach the anal fin origin, and have two or three detached rays at the bottom of the fin. Their body is covered with rough scales.

The Splitnose Searobins are found over and within sandy and muddy bottoms at depths between 55 and 655 feet. They reach a maximum length of 17.5 cm (6.9 inches).They are more active and feed at night; during the day they are found submerged in sand.  The Splitnose Searobins are poorly studied and very little is known about their behavioral patterns.

In Mexican waters the Splitnose Searobins are found from Todos Santos southward along the extreme southwest coast of Baja, as established by a fish in my possession, throughout the Sea of Cortez, and along the coast of the mainland south to Guatemala.

The Splitnose Searobin is most likely confused with the Chevron Searobin, Bellator loxias (yellow and orange bars on flank) or the Nakedbelly Searobin, Bellator gymnostethus (short first dorsal spine).

Due to their size and rarity, the Splitnose Searobins are of limited interest to most. They are a frequent by-catch of deepwater shrimp trawlers around the tip of Baja.

Splitnose SearobinSplitnose Searobin

Splitnose Searobin, Bellator xenisma. Fish provided by the commercial fishermen of greater Los Cabos area, Baja California Sur, June 2009. Length:13.0 cm (5.1 inches). Fish identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, CA.