Breeding Akysis vespa

Breeding notes for Akysis vespa, the Asian wasp catfish: a nano Salween-basin catfish with one documented spawning triggered by a sharp temperature drop.

Overview

Akysis vespa is a nano catfish of the family Akysidae, reaching only about 25-31 mm standard length. Seriously Fish records it as endemic to the headwaters of the Salween River basin on the Myanmar-Thailand border, in the Megathat stream drainage in Myanmar and the Hanthayaw River in Thailand. It is a primarily nocturnal micropredator feeding on small crustaceans, worms, insect larvae and zooplankton, kept at 16.5-23.5 degrees Celsius and pH 6.0-7.5.

Spawning Behavior & Trigger

According to Seriously Fish, a successful spawning was recorded only once, in the original species description paper. It was apparently triggered by a significant decrease in temperature of around 7 degrees Celsius, consistent with the cool, seasonal nature of its hill-stream habitat.

Egg & Fry Care

In that single documented event, the eggs hatched in 4 days, the fry absorbed their yolk sacs within 10 days, and adult patterning developed within 23 days. No other rearing details are documented.

Common Challenges

Sexual dimorphism is unreported for the species, and the only spawning on record comes from the type description rather than repeated aquarium success, so any attempt should be regarded as experimental.