Chocolate frogmouth catfish

Care at a glance

Overview

The chocolate frogmouth catfish is a sit-and-wait ambush predator that spends almost all its time motionless on the bottom, half-buried and disguised as a lump of waterlogged wood. It is not aggressive, but its mouth is enormous and it will inhale any fish or shrimp that wanders close, sometimes prey nearly its own length, so keep it alone or only with fish far too big to swallow. It rarely chases food, so target-feed sinking meaty items such as strips of fish, prawn, and earthworms near its head. Give it a soft sand bed, leaf litter, and shade, and keep it in a tank of around 170 liters or larger.

In the wild

The chocolate frogmouth catfish comes from slow, shaded waters in Thailand and nearby parts of Southeast Asia, where it lies among leaf litter and sunken wood on the beds of soft, acidic streams and swamps. Keep it warm, from around 24 to 28 C, with a pH between 6 and 7.5 and gentle flow. A thick layer of leaf litter over sand, plus driftwood and dim lighting, lets it bury and camouflage itself the way it does in the wild. Tannin-stained water suits it and deepens its chocolate colour.

Good to know

The chocolate frogmouth catfish is one of only a handful of species in the family Chacidae, the frogmouth or squarehead catfishes. It grows to around 20 cm, most of which is a broad, flattened head ending in a vast, upturned mouth. It hunts by camouflage and ambush, and can twitch small barbels near its jaws to lure curious fish within range before engulfing them in a sudden gulp. Its wild breeding is poorly known, and it has not been bred in aquariums.

Did you know

The chocolate frogmouth catfish is a living ambush trap. It sits motionless, looking exactly like a piece of sodden bark, and can wiggle small barbels near its huge mouth like bait, then swallow any fish that comes to investigate in a single sudden gulp.

Related species

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• 

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