Saddled Blenny, Malacoctenus triangulates

Saddled Blenny, Malacoctenus triangulates, Male. Underwater photographs taken in coastal waters off Bonaire, December 2019. Photographs, and identification courtesy of Bob Hillis, Ivins, Utah.

Saddled Blenny, Malacoctenus triangulatus, Male. Underwater photographs taken with coastal waters off Cozumel Island, Quintana Roo, March 2021. Photographs and identification courtesy of Marina Sutormina, Stockholm, Sweden.

The Saddled Blenny, Malacoctenus triangulates, is a member of the Labrisomid Blenny or Labrisomidae Family, that is known in Mexico as trambollo ensillado. Globally, there are eighteen species in the genus Malacoctenus, of which fourteen are found in Mexican waters, six in the Atlantic and eight in the Pacific Ocean.

The Saddled Blenny has a shortened elongated body with a uniform depth throughout that tapers gradually at the rear into the tail. They are an overall pale white to pale yellow in color. They are easily recognized by three to five dark brown-reddish inverted triangles along their sides. They also have a bar at the end of the caudal peduncle and a dark spot and the front base of the dorsal fin. The males have clear fins; the females have densely spotted fins. Their head has a few small dark spots and their body is covered with scattered dots. Their head is slender with two to four branched cirrus over the nostril, two to eight branched cirrus over the eyes, and four to thirteen branched cirri on each side of the nape. Their mouth is small, opens at the front, and is equipped with one row of large teeth on the upper jaw. Their anal fin has 2 spines and 20 to 22 rays; their caudal fin is rounded; and, their dorsal fin has 20 or 21 spines and 11 or 12 rays with a notch in between; they have 14 pectoral rays; and their pelvic fins have 1 spine and 3 rays and are found before the pectoral fins. They are covered with small scales.

The Saddled Blenny is a small shallow water coastal species normally found in shallow water but also at depths up to 40 m (130 feet). They are found in sheltered areas within coral reefs and rocky shores often in crevices or among weed and rubble. They reach a maximum of 7.5 cm (3.0 inches) in length. They are diurnal highly territorial predators that feed mostly on benthic crustaceans including small crabs. Reproduction is oviparous with females depositing eggs in protected areas that are guarded by the males. Their eggs are a favorite of and heavily preyed upon by the Bluehead Wrasse, Thalassoma bifasiatum. The Saddled Blenny 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 Saddled Blenny is a resident of Mexican waters of the Atlantic Ocean with the exception that they are absent from the extreme northwestern Gulf of Mexico, from the Texas border to Tuxpan, Veracruz.

The Saddled Blenny is the most conspicuous fish in most environments due the bold pattern of dark triangles on their sides. They are mostly likely confused with the Barfin Blenny, Malacoctenus versicolor (5 wide bars that extend into the dorsal fins, the Goldline Blenny, Malacoctenus aurolineatus (lower body with thin stripes) and the Rosy Blenny, Malacoctenus macropus (covered with numerous dark and like spots).

From a conservation perspective the Saddled Blenny is currently considered to be of Least Concern with stable, widely distributed populations. They are small in stature and of limited interest to most. They are utilized by the aquarium trade on a limited basis.