Pearly Razorfish, Xyrichtys novacula
Pearly Razorfish, Xyrichtys novacula, Initial Phase (IP), Female. Fish caught from shore in Fuerteventura, Canary Islands, Florida, March 2018. Length: 18 cm (7.1 inches). Catch, photograph and identification courtesy of Kenneth Tse, Toronto, Ontario, Canada.
Pearly Razorfish, Xyrichtys novacula, Terminal Phase (TP), Male. Fish caught is coastal waters off Fuerteventura, Spain, June 2015. Length: 18 cm (7.1 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
The Pearly Razorfish, Xyrichtys novacula, is a member of the Wrasse or Labridae Family, that is also known as the Cleaver Wrasse and in Mexico as cuchillo perlino. Globally, there are twenty-seven species in the genus Xyrichtys, of which four are found in Mexican waters, three in the Atlantic and one in the Pacific Ocean. Their common name razorfish, stems from their compressed bodies that have a sharp leading edge on their forehead and snout that allows quick entry into the sand.
The Pearly Razorfish has an elongated very laterally compressed body with a depth that is 35% to 39% of standard length. Females and males of the Initial Phase (IP) are pale gray to pinkish brown with distinct pearly marks on the on the sides of the belly. Terminal Phase (TP) males are pinkish brown dorsally transitioning to pale ventrally; their lower head has thin blue bars and the sides of the belly have scales with thin blue bars; some TP males have a diagonal reddish-brown bar on their sides behind the pectoral fin. Juveniles are pale gray with four irregular brown bars on the body and tail base and a brown bar that runs from the head to the front of the dorsal fin. Their head is flattened with a very steep nearly vertical profile with a very blunt snout and a protrusible mouth opening in the front, equipped with very sharp teeth; they have a fleshy longitudinal keel at the front, small eyes are set very high on the head and they have a pair of long curved canine teeth anteriorly on each jaw. Their anal fin has 3 spines and 12 rays; their caudal fin is slightly rounded; their dorsal fin has 2 prolonged spines, which diminish in length with maturity, 7 normal spines, and 12 rays with a long base; their pectoral fins have 12 rays, and their pelvic fins are pointed. They have 18 to 21 gill rakers. They are covered with scales. Their lateral line has two sections, with the rear section on the tail base.
Pearly Razorfish are found on open sand near seagrass beds and reefs and will quickly bury themselves head first in sand as a defense mechanism. They are found as single individuals or in small groups. They reach a maximum of 38 cm (15 inches) in length. They are found between depths of 5 m (16 feet) and 110 m (360 feet) being found at greater depths during the winter. They are diurnal and opportunistic feeders that consume small invertebrates including crabs, crustaceans, echinoderms, mollusks and shrimp. They are protogynous hermaphrodites that change sex midlife with the sexes differing in color, head shape and the length of the pelvic fins. Nests are built from coral debris in coral reef habitats. They have lifespans of eight years. The Pearly Razorfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.
The Pearly Razorfish is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico, with the exception that they are absent in the eastern portion, and the east coast of the Yucatán Peninsula in the Caribbean.
The Pearly Razorfish is a fairly easy identification that is most likely confused with the Bluelip Parrotfish, Cryptotomus roseus (body depth 22-25% of SL) and the Rosy Razorfish, Xyrichthys martinicensis (rounded head profile).
From a conservation perspective the Pearly Razorfish is currently considered to be of Least Concern with stable, widely distributed populations. Although small in stature they are fished commercially in some areas, being caught by hook and line and via trawls. In some locations they are considered to be a popular game fish and are also utilized as live bait, targeting large game fish. They are also utilized by the aquarium trade.