Porehead Blenny

Porehead Blenny, Labrisomus multiporosus

The Porehead Blenny, Labrisomus multiporosus, whose common Spanish name is trambollo cabeza porosa, is a species in the family Labrisomid Blenny or Labrisomidae Family, known collectively as trambollos in Mexico. Globally, there are twenty-seven species in the genus Labrisomus, of which thirteen are found in Mexican waters, nine in the Atlantic and four in the Pacific.

The Porehead Blennies have shortened elongated robust bodies with a uniform depth throughout that tapers gradually at the rear into the tail. They are tan to brownish in color with heavy dark brown mottling and irregular bars on their sides. A key to identification is a pair of oblique bands across their cheeks that turn into horizontal lines. They have prominent dark spotting on their caudal, dorsal, and pectoral fins. Their dorsal fin has an ocellus at the front. Their head is broad with a blunt snout, large eyes, a branched cirrus over each eye, and several branched cirri on each side of the nape. Their head is also densely covered with sensory pores after which they are named. Their mouth is large, opens at the front, and is slightly oblique; it is equipped with one row of small teeth on the upper and lower jaws and includes teeth on the roof of the mouth. Their anal fin has two spines and 17 or 18 rays; their caudal fin is square; and their dorsal fin has 17 to 19 spines and 10 or 11 rays with a deep notch in between. They are covered with small smooth scales.

The Porehead Blennies are a shallow water coastal species found within weed-covered rocky shores at depths up to 65 feet. They reach a maximum length of 18.0 cm (7.1 inches). 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. Very little is known about their behavioral patterns.

In Mexican waters the Porehead Blennies are found in all waters of the Pacific with the exception that they are absent from Guerrero Negro northward along the central and northwest coasts of Baja.

The Porehead Blenny can be easily confused with a series of Blennies including the Green Blenny, Labrisomus striatus (brown coloration; brown spots and thin stripes; two oblique bars on cheeks; front dorsal spines are shortest; dark spots on base of anal, caudal, and dorsal fins) and the Largemouth Blenny, Labrisomus xanti (head covered with numerous small white spots).

Although plentiful, the Porehead Blennies are of limited interest to most, due to their small size.

Porehead Blenny, Labrisomomus multiporosus: Caught from shore at Km 21, Cabo Real, Baja California Sur, November 2008. Length: 13.8 cm (5.4 inches).

Porehead Blenny, Labrisomomus multiporosus. Fish caught from shore at Km 21, Cabo Real, Baja California Sur, November 2008. Length: 13.8 cm (5.4 inches).

Porehead Blenny, Labrisomus multiporosus. Fish caught from a coastal tidal pool, Mazatlán, Sinaloa, April 2015. Length: 12.2 cm (4.8 inches). Catch and photo courtesy of George Brinkman, Guelph, Ontario, Canada.

Porehead Blenny, Labrisomus multiporosusFish caught with Jimmy Camacho, Jimmy’s Sportfishing, Puerto Adolfo Lopez Mateos, Baja California Sur, (Jimmyhcamacho@gmail.com, 613-114-0761; 612-204-1960) within the coastal waters of Magdalena Bay, Baja California Sur, March 2017. Length: 13.1 cm (5.2 inches).