细颈鲶 · Pygmy Driftwood Catfish

Overview

The small Trachelyichthys exilis is peaceful toward its own kind and is best maintained socially. Unlike many related catfishes, it usually eats during daylight. Planted shelter and softened light should be balanced with open swimming room.

Distribution & habitat

It originates from the Nanay drainage in Peru, occupying the river and its tributaries.

Aquarium setup

Use a footprint around 60 × 38 cm. Dense vegetation helps it show good color, but retain corridors between planted areas. Floating plants can reduce intense direct light and create a more subdued setting.

Diet & feeding

It favors live and frozen offerings including bloodworms, earthworms, and prawn, while most individuals also accept small pellets or flakes. Daytime feeding is normal. Observe actual feeding behavior rather than automatically postponing every meal until late at night.

Behaviour & compatibility

Conspecific aggression is absent, and a group is preferable. Appropriately sized peaceful fishes make suitable companions. Very tiny fry are an exception to its generally safe community behavior, so a calm temperament should not be treated as protection for nursery fish.

Sexual dimorphism

Males possess a heavily modified anal fin used during mating, functionally comparable to a livebearer's gonopodium. Females become noticeably rounder when carrying eggs.

Breeding

Aquarium reproduction has been reported, and fertilization is internal. Specific spawning triggers and nursery conditions remain uncertain. Although the mating structure resembles that of livebearers in function, this does not establish an equivalent reproductive mode.

Notes

It closely resembles Trachelyichthys decaradiatus. In this species the eye lies farther forward, and the humeral projection extending behind the gill cover is longer and narrower. Both appear infrequently in the hobby, making structural examination more useful than relying entirely on sales labels.