Largemouth Blenny: Big Head, Wide Mouth, Perfect Camouflage

The largemouth blenny is a stout, big-headed little fish with a wide mouth and mottled brown coloring that melts right into the rocks. It likes to perch out in the open, trusting its camouflage, which makes it a fun one to find. Here's how to spot one snorkeling near Jacó, plus five fun facts.

Largemouth Blenny · Labrisomus xanti

How to spot the largemouth blenny near Jacó

Scan the tops and sides of algae-covered rocks in the shallows. The largemouth blenny props itself up on its fins in plain sight, but its mottled brown pattern makes it look like just another lump of rock until it moves. Look for the big head, the wide mouth, and the fringed tabs above its eyes.

5 fun facts about the largemouth blenny

• Camouflage over speed. Instead of hiding in a hole, it trusts its mottled brown coloring to blend into the rock, sitting still in the open and relying on not being seen.
• A big mouth for a reason. That wide mouth lets it snap up a varied diet of small crabs, shrimp, snails, and other little creatures it finds on the reef.
• Feathery eyebrows. Branched tabs called cirri sit above its eyes and nostrils, helping break up its outline against the rough, algae-covered rock.
• A rock-top perch. Like other blennies, it rests on its fins on the rock rather than hovering in open water, giving it a propped-up, alert look.
• A sturdy little fish. Stocky and well-built for its size, it's one of the larger, more robust blennies you'll come across in the shallows.

The largemouth blenny is just one of many characters down there. See the whole cast in our Snorkel Jaco fish directory, or read real guest photos and reviews on the Snorkel Jaco reviews.