Largehead Moray

Largehead Moray, Uropterygius macrocephalus

Largehead Moray, Uropterygius macrocephalus, Juvenile. Caught by hand alive and feisty, on the beach above the water line well before first light, at Km 21, Cabo Real, Baja California Sur, July 2006. Length: 23 cm (9.1 inches).

Largehead Moray, Uropterygius macrocephalus., Juvenile. Fish caught by hand out of a tidal pool, Km 17, El Tule, Baja California Sur, February 2018. Length: 25.5 cm (10 inches); Tail: 51%.

Largehead Moray, Uropterygius macrocephalus, Juvenile. Caught by hand alive and feisty, on the beach above the water line well before first light, at Km 21, Cabo Real, Baja California Sur, April 2021. Length: 26 cm (10 inches).

Largehead Moray, Uropterygius macrocephalus. Fish caught from coastal waters off Point Palmilla, Baja California Sur, August 2015. Length: 45 cm (18 inches). Tail: 47%.

The Largehead Moray, Uropterygius macrocephalus, is a member of the Moray and Snake Moray Eel or Muraenidae Family, that is also known as the Needletooth Moray and in Mexico as morena cabezona. This fish is also known as the Needletooth Moray. Globally, there are twenty-one members in the genus Uropterygius, of which four are found in Mexican waters, one in the Atlantic and three in the Pacific Ocean.

The Largehead Moray has a slender elongated body that tapers gradually and is compressed at the rear. They are brown in color with irregular pink mottling. They lack the black spot around the gill coverings found in many Morays. The tip of their tail has a white or yellow coloration. Their head has a short, stout, and rounded conical snout. Their eyes are small and centered over the middle of their mouth, which is equipped with sharp slender conical teeth. Their front nostril is tubular; their posterior nostril is a small hole with a raised rim above the front of the eyes. Their anal and dorsal fins are very small and visible only as skin-covered ridges near the tip of the tail. Their tail is equal in length or longer than the head and trunk.

The Largehead Moray is found as a solitary individual that inhabits shallow reef areas and are found within cracks and crevices in the subtidal zone at depths up to 14 m (45 feet). They reach a maximum length of 47 cm (19 inches). They are nocturnal ambush predators with poor eyesight that utilize their keen sense of smell to seek out prey, consuming small fish and invertebrates including crab, octopus, and shrimp. Reproduction is viviparous with eggs and sperm broadcast into the water generating pelagic eggs and larvae that drift in oceanic currents before settling out on the bottom. The Largehead Moray is an uncommon and 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 Largehead Moray is a resident of Mexican waters of the Pacific Ocean but has a limited distribution  being found only in the lower half of the Sea of Cortez and along the coast of the mainland south to Guatemala.

Due to the unique mottling covering its sides (pictured above), the Largehead Moray cannot be confused with any other species.

From a conservation perspective the Largehead Moray is currently considered to be of Least Concern with stable, widely distributed populations. They are very seldom, seen by humans. When encountered they are visually most intimidating but are very timid and not harmful and are only known to bite humans on rare occasions. They are caught and retained on occasion by artisanal fishermen and out of heavy rock structure by recreational anglers but are normally a “catch and release”. They are utilized by the aquarium trade on a limited basis.