Blacklip Dragonet, Synchiropus atrilabiatus
The Blacklip Dragonet, Synchiropus atrilabiatus, whose common Spanish name is dragoncillo de asta, is a species in the Dragonets or Callionymidae Family, known collectively as dragoncillos in Mexico. Globally, there are one hundred eighty one species in the Callionymidae family placed into eighteen genera. There are thirty four species in the genus Synchiropus, and only this species found in Mexican waters, it from the Pacific.
The Blacklip Dragonets have elongated flattened bodies. Live fish have reddish brown upper bodies covered with numerous small black spots. They have dusky fins and a dark oval ocellus with a partial white ring between the last two dorsal spines of the dorsal fin. This ocellus is darker and larger in males. Their anal fin has a broad red-black band near its white margin. Their caudal, pectoral, and pelvic fins have yellow tinges; in males these fins also have bands of dark spots. The margin of their top jaw is black. They have a long and depressed head with a short pointed snout and large eyes set on top of the head. Their mouth is small and oblique with the top jaw being protrusible. They have very small gill openings with a large spine on the preopercle. Their anal fin has seven or eight rays; their caudal fin is large and rounded in females and has a central point in males; their dorsal fin has four standalone spines (decreasing in height from front to back in males and of equal length in females) and eight or nine rays; and their pectoral fins are rounded. They have no scales.
The Blacklip Dragonets are found demersal over soft bottoms at depths up to 770 feet. They reach a maximum length of 16.7 cm (6.6 inches). Adults reside in sand and mud habitats, whereas juveniles are pelagic and can be found mid-water up to 200 miles offshore. Adults feed on small benthic invertebrates by walking the ocean floor on their pelvic fins. Reproduction is oviparous with pelagic eggs and larvae. They are an uncommon poorly studied species and very little is known about their behavioral patterns.
In Mexican waters the Blacklip Dragonents are found in all waters of the Pacific with the exception that they are absent from north of La Paz in the Sea of Cortez.
The Blacklip Dragonet closely resembles the sculpins from the Cottidae family in body shape (large gill openings) but is unique due to the numerous small spots on its body, the ocellus spot on its dorsal fin, the black coloration of the lower half of its anal fin, and the black margin of its upper lip.
Due to their small stature, the Blacklip Dragonets are of limited interest to most. They are seldom seen by humans but may be encountered by divers on rare occasions over sandy patches surrounded by coral and rocky reefs.
Blacklip Dragonet, Synchiropus atrilabiatus. Fish caught from coastal waters off Point Palmilla, Baja California Sur, November 2010. Length: 3.1 cm (1.2 inches). Provided in pristine condition via regurgitation by a 46 cm (18 inch) Jack Mackerel. Identification courtesy of Dr. Phil Hastings and H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, CA.