Horseshoe catfish

Tetranematichthys wallacei

Also known as Wallace's driftwood catfish

FreshwaterFish

Horseshoe catfish (Tetranematichthys wallacei) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 6.0–7.5
Adult size: 8.3 in (21 cm)
Minimum tank: 79 gal (300 L)
Temperament: Mostly peaceful
Social behavior: Solitary
Tankmates: Tankmates with caution
Swim level: Bottom
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Upper Negro and Orinoco basins
Family: Auchenipteridae

Overview

The horseshoe catfish is a secretive, leaf-mimicking predator best kept on its own. It lies still among dead leaves and wood by day, doing a convincing impression of a sunken leaf, and becomes active in the dark. It is calm toward fish too big to eat but will take any tankmate small enough to fit in its mouth, so keep companions well above swallowing size and choose them with care. Feed meaty foods such as earthworm, prawn, and chunks of fish or mussel. Give it a dimly lit tank of around 300 liters or more with deep leaf litter, wood, and quiet corners to lie up in.

In the wild

Tetranematichthys wallacei haunts blackwater in the upper Negro and Orinoco basins, lying among drifted leaves and submerged wood in soft, dark, acidic water. Recreate that with a bed of leaf litter, plenty of driftwood, tannin-stained water, and low light. Keep it warm and soft at 23–28 C and around pH 6.0–7.5, with gentle flow, so it can settle in and ambush from cover.

Good to know

Tetranematichthys wallacei is a driftwood catfish, family Auchenipteridae, reaching about 21 centimeters. It is built to mimic a dead leaf, and breeding males grow a tall, thorny dorsal fin and fertilize the female internally with a modified anal fin. Aquarium spawning is not recorded. The species honors the naturalist Alfred Russel Wallace.

Did you know

It is named for Alfred Russel Wallace, who explored the Rio Negro in the 1850s. On his voyage home his ship caught fire and sank, taking most of his South American collection with it, though he survived and went on to co-found the theory of natural selection.