Paracanthocobitis pictilis · Cherry-fin Loach

Overview

A bold loach, Paracanthocobitis pictilis develops reddish snout and fin coloration in breeding males. It can be less peaceful than some relatives, with excessive male aggression reported when kept alone or in small numbers. Group composition and robust companions matter.

Distribution & habitat

The core range is the Ataran, flowing from Thailand into Myanmar within the Salween system. A formerly included Mae Khlong population was separated as another species. Nearby Hanthayaw records may also belong here but remain tentative.

Shaded clear riffles and flowing stretches provide high oxygen, with occasional use of deeper pools. Sand, gravel, rocks, boulders, leaves, wood, and roots structure the habitat; plants occur in quieter patches.

Aquarium setup

Build a river-style layout with mixed rounded stones, sand, fine gravel, and boulders. Branches provide numerous crevices and shaded areas, with robust attached plants if desired. Use a biologically mature aquarium because stable conditions are essential.

External filtration, circulation pumps, or aeration should maintain high oxygen and movement while preventing waste accumulation. Break sight lines so subordinate fish can retreat beyond a dominant individual’s view.

Diet & feeding

A diet of small animals is considered probable, and examined stomach contents included chironomid and mayfly larvae. Combine sinking dry products with regular small live or frozen water fleas, Artemia, and bloodworms.

Behaviour & compatibility

A mixed-sex group of at least six helps distribute male attention and gives subordinates respite. Choose similarly sized, active, robust companions adapted to comparable conditions. Some males become strongly territorial and harass other species when kept in low numbers, so the mild reputation of relatives is not a reliable guide.

Sexual dimorphism

Males have a deep groove below the eye, thickened anterior pectoral rays with small tubercles, and additional roughened patches around the cheek. Females lack the prominent structures, though some have a shallow groove. Breeding males redden around the snout and fins, while gravid females deepen in body.

Breeding

Reproduction is unrecorded.

Notes

The body lacks the large flank blotches of some relatives. Several dark tail bands accompany a small vertical or crescent-shaped mark high on the tail base. Older trade identifications should not automatically expand the known range.