Longnose Eagle Ray, Myliobatis longirostris
Longnose Eagle Ray, Myliobatis longirostris. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, July 2009. Disc width: 60 cm (2 feet 0 inches) by 32 cm (13 inches). Tail: 80 cm (2 feet 7 inches). Identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, California.
Longnose Eagle Ray, Myliobatis longirostris. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, August 2013. Disc width: 66 cm (2 feet 2 inches); Disc length: 42 cm (16.5 inches). Note that the tail was surgically removed at the time of the catch to avoid human contact with the venomous spine. Identification courtesy of Dr. Ross Robertson, Smithsonian Institute, Panama City, Panama.
The Longnose Eagle Ray, Myliobatis longirostris, is a member of the Eagle Ray or Myliobatidae Family, that is also known as the Snouted Eagle Ray and in Mexico as águila picuda. Globally, there are eleven species in the genus Myliobatis, of which five are found in Mexican waters, one in the Atlantic, three in the Pacific, and one in both the Atlantic and the Pacific Oceans.
The Longnose Eagle Rays has a flattened rhomboidal disc-shaped body that is approximately 1.75 times wider than they are long. They are dark reddish brown dorsally and their undersides are dusky white with gradual to dark edges. Their head is large, bulbous, elevated, and protruding with a long pointed snout. Their head and eyes are behind the origin of the pectoral fins; these fins are long and form equivalent triangles with pointed tips and concave rear edges. Their mouth has flat, pavement-like plates of teeth arranged in 7 series. They have a single dorsal fin at the base of their slender whip-like tail, which is approximately twice the length of the disc and contains a long venomous spine with an injecting barb at the base used for self-defense. They have smooth skin without denticles.
The Longnose Eagle Ray is found inshore over sandy bottoms at depths up to 64 m (210 feet). They reach a maximum disc width of 97 cm (3 feet 2 inches). Reproduction occurs via ovoviviparity with internal fertilization. Embryos are initially fed on yolk then receive additional nourishment from the mother by indirect adsorption of uterine fluid enriched with mucus, fat, and protein. Litter and pup sizes are unknown. The Longnose Eagle Ray is an exceedingly rare and poorly studied species with very limited information available about their lifestyle and behavioral patterns including specific details on catch, age, growth, longevity, movement patterns, diet, habitat use, reproduction, and range.
The Longnose Eagle Ray is a resident of Mexican waters of the Pacific Ocean but is poorly documented and are known from Guerrero Negro , Baja California, southward along the central and southwest coasts of Baja and within the Sea of Cortez.
The Longnose Eagle Ray can be confused with the Bat Rat, Myliobatis californica (much shorter non-projecting head) and the Rough Eagle Ray, Pteromylaeus asperrimus (disc width greater than twice the disc length; striping on underside; longer snout).
From a conservation perspective the Longnose Eagle Ray is currently considered to be NEAR THREATENED. This assignment is based on infrequent catches by artisanal fishermen, the overall population decline of many myliobatid rays, and an intense and unregulated fishery. The Longnose Eagle Ray is scarce and seldom caught by artisanal fishermen. They do show up occasionally as a by-catch of demersal shrimp trawls, longlines, and gill nets and are normally discarded with a high mortality rate. There is no commercial fishery for the Longnose Eagle Ray. Note: Rays of the genus Myliobatis have tails with a venomous spine. Although the Longnose Eagle Rays are exceeding rare, they are potentially dangerous as they can inflict wounds with intense pain and slow recovery. Approximately 1,500 stings from stingrays are reported annually.