Featured Elasmobrach – Longnose Eagle Ray
Category : Featured Elasmobranch
Illustration courtesy FAO
Longnose Eagle ray
Myliobatis longirostris (Applegate and Fitch, 1964)
Identification: An eagle ray with a pointed, shovel-shaped snout; disc lozenge-shaped, with narrow, acutely pointed wing tips. Total length, including tail, about twice disc width. A single rounded tubercle present above each eye. Midback line with 19 tubercles present halfway between the head and the tail. Two caudal spines located directly behind the dorsal fin; dorsal fin height about one-half its length. Adult male claspers lack spines and hooks. The dorsal surface is dark reddish brown, while the ventral surface is dusky white, grading to black on the edge of the rostrum, wing tips, pelvic fins, and claspers.
Size: Maximum disc width 95 cm; female size at maturity is about 74 cm disc width, while male size at maturity is about 54 cm disc width. Size at birth is unknown.
Distribution: Occurs from central Baja California throughout the Gulf of California, Mexico. It has been reported from Peru, and likely ranges through Central America, although its exact distribution is unknown.
Habitat: This ray occurs on soft or sandy bottoms, from the surface to about 60 meters in depth.
Biology: A poorly known species, the reproductive mode is viviparity, as in other myliobatids, but nothing is known about litter size, gestation, age at maturity, or diet.
General Interest: Although not targeted directly, Longnose eagle rays are vulnerable as bycatch and are listed as Near Threatened by the IUCN Redlist. They are often incidentally caught in trawl fisheries, gillnets, and longlines. Mexican shrimp trawlers are an example of a fishery that lands them. As so little is known about the distribution and biology of this species, it could be highly impacted by fishing activities.
By: Kelley Andrews
Pacific Shark Research Center
Moss Landing Marine Laboratories