Moray Eel Family  – Muraenidae

There are currently TWENTY-FIVE members of the Moray Eel or Muraenidae, seven from the Atlantic Ocean and eighteen from the Pacific Ocean,  are presented in this website:

FROM THE ATLANTIC (7):

FROM THE PACIFIC (18):

The Morays and Moray Snake Eels belong to the Muraenidae Family that includes one hundred ninety-nine global species that have been placed in sixteen genera. There are thirty-seven family members residing in Mexican waters, sixteen in the Atlantic and twenty-one in the Pacific Ocean. They are known in Mexico’s fishing areas as morenas. Morays are notoriously difficult to identify; some important characteristics to observe include fin position, tail length, jaw and dentition, nostril profile, and color pattern, noting that color also varies with fish maturity.

The Morays are found globally in both marine and brackish waters in all tropical and temperate seas. They are medium to large fish ranging from 11.5 cm (4.5 inches) to 4 m (13 feet) in length and up to 30 kg (66 lbs) in weight. Most are brown to dark brown in color and many have distinctive patterns of spots, bars and/or reticulations. They have very elongated muscular compressed bodies. Their heads have snouts that vary from long to short and slender to heavy. They have small eyes, elevated napes, tubular front nostrils, rear nostrils that appear as a hole or tube over or before the eyes, large mouths with teeth that vary from sharp to needle-like fangs to flat molars that are found either in rows on the sides or on the roof of the mouth. They have a second set of jaws (pharyngeal jaws) that can be extended into the mouth to grasp prey. Their heads have 3 pores near the tip of the snout, 4 along the top jaw, and 6 on the lower jaw. Their gill openings are a hole or a slit in their mid-side. Their well-developed anal and dorsal fins originate before the gill openings and are continuous with the caudal fin. They do not have pectoral fins and most do not have pelvic fins. They also do not have scales. They have smooth skin covered with a protective mucus.

Morays are benthic and reside from the shoreline to depths up to 457 m (1,500 feet) where they hide in rock crevices and rarely emerge during daylight hours. They have limited eyesight and depend on their acute sense of smell to seek out prey. They open and close their mouths frequently, an action required for respiration. They are night time predators preying crab, fish, octopus, shrimp, and squid. In turn they are preyed upon by barracudas, groupers, and sea snakes. 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.

Morays are generally poorly studied and poorly characterized. They are shy and secretive fish that prefer to flee than confront human intruders. They are caught by spear, hook and line, dredges, longliners, traps, and trawls. When caught by hook and line they are notorious for coiling and creating massive “bird nests” out of the fishing line used to catch them. They are not targeted commercially but are obtained as a by-catch and sold in local fish markets on a very limited basis. They are used for human consumption by some cultures but some of the larger species contain ciguatoxin. Some species are also used as aquarium fish. In Australia they are a major focus of dive trips and are known to “bite the hand that feeds them” and to attack if provoked or if their habitat is threatened. They date to the Tertiary Miocene Period, 50 million years ago.

Muraenidae Sp. Fish collected within the sand dunes of Puerto Adolfo Lopez Mateos, Baja California Sur, January 2017. Length: 66 cm (2 feet 2 inches). Collection and photo courtesy of Brad Murakami, Surrey, British Columbia, Canada.  Identification courtesy of Gary Nafis, Californiaherps.com.