Breeding the Sky Blue Crayfish (Cherax snowden)

Breeding the West Papuan Cherax snowden, described in 2015: a berried female broods eggs and young directly under her tail, with no planktonic larval phase.

Overview

Cherax snowden was described in 2015 by Lukhaup, Panteleit and Schrimpf and named after Edward Snowden. It comes from the Oinsok River drainage in the Sawiat District of the Vogelkop (Kepala Burung) Peninsula, West Papua, Indonesia. Its body shows green to bluish tones with orange-tipped claws; it had circulated in the trade as 'orange tip' and was earlier confused with Cherax holthuisi. Males reach about 10 cm and females about 7 cm. It breeds as a berried female with direct development.

Sexing

Sex is determined from the genital openings on the underside: males bear paired papillae at the base of the last pair of walking legs, females show openings at an earlier pair. Males of this species also grow larger than females and tend to have heavier claws, which can support a tentative field guess before the underside is checked.

Conditioning

Stable water within tolerated ranges and a mixed omnivorous diet bring adults into breeding condition. As documented for the genus, fertilised eggs develop inside the female for roughly four to six weeks and then move to the exterior of her body, where they are carried on the tail.

Breeding Setup

Provide a spacious tank with many caves so the pair can establish space and a berried or moulting female can hide. During mating the pair grapples and the male transfers sperm; the female then incubates the eggs on her tail until hatching.

Berried Female & Young

Hatchlings remain attached under the female's abdomen and emerge as fully formed miniature crayfish, since development is direct rather than larval. They stay with the mother for a time before dispersing; relocating the female after release reduces predation by tank mates.

Common Challenges

Aggression between adults and cannibalism of soft, newly moulted juveniles are the main hurdles, so dense cover and several feeding stations help. The species is not compatible with fish, shrimp or plants, so a species-only tank is the practical choice.