California Skate

California Skate, Raja inornata

The California Skate, Raja inornata, whose common Spanish name is raya de California, is a species in the Skate or Rajidae Family, known collectively as rayas in Mexico. Globally, there are thirty-two species in the genus Raja, eight of which are found in Mexican waters, three in the Atlantic and five in the Pacific.

The California Skates are shaped as large flattened diamond-shaped discs, which include the head, body, and pectoral fins. The disc length is similar to the width and the tail is approximately 50% of the disc length. Their head and “wings” are pointed. Their coloration is olive-brown on the back and off-white on the underside. Some fish have dark ocelli spots at the base of each pectoral fin. Their head is long and sharply pointed with a rigid snout with concave sides. They have large spiracles behind their eyes, deeply notched pelvic fins with two distinct lobes with the rear lobe being the largest, two small dorsal fins, and no caudal fin. They have one row of spines along the tail that extends into the pelvic fins; on some fish the row of spines extends to the mid-back. The dorsal side of the disc is covered with small scattered denticles.

The California Skates are found over sandy bottoms at depths between 45 and 5,250 feet. They reach a maximum length of 75 cm (30 inches). They consume shrimp, polychaete worms, and small benthic fish. In Mexican waters they are found from along the entire west coast of Baja and throughout the Sea of Cortez. They are absent from along the coast of the mainland south to Guatemala. They are oviparous and lay large eggs in black or dark green leathery shells, known as Mermaid’s Purses, which have an oblong outline with a hollow tendril at each corner which is used to attach to marine objects. They are produced in pairs with each case containing up to seven embryos. This species is fairly rare with a limited distribution and very little is known about its behavioral patterns.

In Mexican waters the California Skate has a limited distribution being found only along the entire west coast of Baja and throughout the Sea of Cortez.

The California Skate can be confused with the Equatorial Skate, Raja equatorialis (tail with multiple rows of spines; thorns on edges of pectoral fins) and the Rasptail Skate, Raja velezi (large thorns on tail; two ocelli spots on back).

The California Skate is taken primarily as a by-catch of deep water shrimp trawls and by shark fishermen on hook and line. They are fairly common and sold commercially on a limited basis. They are considered an excellent food fish and are a major component of fish tacos.

California Skate (1)

California Skate, Raja inornata. First provided by the commercial fishermen of Bahía Kino, Sonora, November 2014. Total Length: 75 cm (30 inches); Disc Length: 50 cm (20 inches); Disc Width: 50 cm (20 inches); Tail: 25 cm (9.8 inches). Photo courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.