Browncheek Blenny, Acanthemblemaria crockeri

Browncheek Blenny, Acanthemblemaria crockeri. Underwater photograph taken in waters within La Paz Bay, La Paz, Baja California Sur, May 2018. Photograph and identification courtesy of Ken Bondy, West Hills, California.

The Browncheek Blenny, Acanthemblemaria crockeri, is a member of the Tube Blenny or Chaenopsidae Family, and is known in Mexico as known tubícola de cachetón. Globally, there are twenty species in the genus Acanthemblemaria, of which six are found in Mexican waters, two in the Atlantic and four in the Pacific Ocean.

The Browncheek Blenny has an elongated body. They are sexually dimorphic with both sexes having a large black-ringed dark brown circle covering the gill cover and many white spots on the head. The front of their dorsal fin is orangish. The males are dark brown with numerous white spots and lines. The females are pale in color with red to orange blotches along the mid-flank, internal white dashes along the vertebral column, and an orange throat. Their head is short with a blunt snout that has strongly developed head spines and three longitudinal rows of spines on each side of the central grove between the eyes. They have one pair of very bushy cirri over the eyes and cirri on the nostrils. Their mouth has two rows of well-developed teeth on the side of the roof of the mouth. Their anal fin has 2 spines and 24 to 28 rays; their first dorsal fin has 23 to 27 spines; their second dorsal fin has 12 to 15 rays; and, their pectoral fins have 13 or 14 rays.

The Browncheek Blenny inhabits abandoned barnacles, mollusks tubes, and worm tubes on rocky reefs in shallow to mid-depth waters at depths up to 60 m (200 feet). They reach a maximum of 6.0 cm (2.4 inches) in length. They enter tail first in the various types of shelter in which they reside and are found with only their head exposed. They feed primarily on zooplankton, benthic invertebrates and small fishes. The Browncheek 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 Browncheek Blenny is a resident of Mexican waters of the Pacific Ocean but has a limited range being found throughout the Sea of Cortez with the exception that they are absent from the extreme northern portion.

The Browncheek Blenny can be confused with the Clubhead Barnacle Blenny, Acanthemblemaria balanorum (lack white spots on the head and sides; gill cover brown ring is much smaller).

From a conservation perspective the Browncheek 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.