Smoothcheek Scorpionfish, Scorpaena isthmensis
Smoothcheek Scorpionfish, Scorpaena isthmensis. Fish caught off the Grand Mayan Pier, Riviera Maya, Cancun, Quintina Roo, February 2019. Length: 11.5 cm (4.5 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.
The Smoothcheek Scorpionfish, Scorpaena isthmensis, is a member of the Rockfish and Scorpionfish or Scorpaenidae Family, that is known in Mexico as escorpión mejilla lisa. Globally, there are fifty-nine species in the genus Scorpaena, of which sixteen found in Mexican waters, ten in the Atlantic and six in the Pacific Ocean.
The Smoothcheek Scorpionfish has a spine-laden compressed elongated oval-shaped body that tapers at both end. The head is very bony with numerous spines and the adults have a well-developed pit on top behind the moderately sized eyes. Overall they are red to brown in color with greenish mottling. The head is brown with dark markings around the gill cover and a prominent dark blotch on the dorsal fin between spines 3 and 7. The iris of the eye is yellow. The caudal fin has three dusky bars, 1 at the base, 1 in the center and 1 at the margin; the outer half of the pelvic fins is dusky, the inner half is pink.
The Smoothcheek Scorpionfish is found from the intertidal zone to depths up to 100 m (330 feet) within rock structure, rubble and sand. They reach a maximum of 26 cm (10 inches) in length. Their anal fin has 3 spines and 5 rays with the third spine being longer than the second; their dorsal fin has 7 spines and 9 rays; and, their pectoral fin has 18 or 19 rays. They are covered with large smooth scales. They have a straight lateral line. They are a classic lie-in-wait ambush predators consuming fish and small invertebrates. The Smoothcheek Scorpionfish 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 Smoothcheek Scorpionfish is a resident of Mexican waters of the Atlantic but has a limited distribution being found only along the east coast of the Yucatán Peninsula in the Caribbean.
The Smoothcheek Scorpionfish is one of twelve scorpionfishes found in coastal waters of the Yucatán Peninsula; however, they are the only one with the prominent spot on the dorsal fin between the third and seventh spines.
From a conservation perspective the Smoothcheek Scorpionfish is currently considered to be of Least Concern with stable, widely distributed populations. They are caught as a by-catch by commercial fishermen with gillnets and cast nets targeting rays but are not sold commercially. CAUTION! As with all Scorpionfish, the Smoothcheek Scorpionfish should be treated as “hazardous” and released as soon as possible, being careful not to allow their poisonous spines to penetrate the skin.