Lumptail Searobin, Prionotus stephanophrys
The Lumptail Searobin, Prionotus stephanophrys, whose common Spanish name is vaca voladora, is a species in the Searobin or Triglidae Family, known collectively as rubios and vacas in Mexico. Globally, there are twenty-three species in the genus Prionotus, fifteen of which are found in Mexican waters, ten in the Atlantic and five in the Pacific.
The Lumptail Searobins have rectangular block-like bodies that are gray brown with white undersides. Their large square bony head is covered with many ridges and spines. Their first dorsal fin has a black blotch between the fourth and fifth spines and their caudal fin and second dorsal fin have rows of black spots. They have moderately deep heads that have wide snouts, slightly projecting snout plates, and long jaws that 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 spines and 12 rays. Their pectoral fins are long, reaching the middle of the second dorsal fin, and have 13 rays; the 3 first free rays are relatively short. Their body is covered with rough scales.
The Lumptail Searobins are found over and within sandy and muddy bottoms at depths up to 840 feet. They are more active and feed at night; during the day they are found submerged in sand. They reach a maximum length of 43 cm (17 inches). The Lumptail Searobins are seldom seen by humans, poorly studied and very little is known about their behavioral patterns.
In Mexican waters the Lumptail Searobin are found in all waters of the Pacific.
The Lumptail Searobin is very similar in appearance to six other Searobins found in Mexican waters of the Pacific, however, it is the only Searobin with a black spot on its dorsal fin and with black pectoral fins, making it easy to identify.
Due to their size and rarity, the Lumptail Searobins are of limited interest to most. They are a frequent by-catch of deepwater shrimp trawlers around the tip of Baja.