Raccoon Butterflyfish (Chaetodon lunula) Breeding Guide

Breeding the raccoon butterflyfish (Chaetodon lunula): a pelagic-spawning reef fish with a planktonic larval stage that is not bred in home aquariums.

Overview

Chaetodon lunula is a butterflyfish (family Chaetodontidae) widespread across the tropical Indo-Pacific from East Africa to the Hawaiian and Marquesan islands, reaching about 20 cm (Wikipedia, FishBase). It is oviparous and shows distinct pairing with monogamous mating during breeding (FishBase). Butterflyfish in general are pelagic spawners whose buoyant eggs and larvae drift in the plankton, so this species is not bred in home aquariums.

Sexing

External sexual dimorphism is not documented in the consulted sources; the species forms monogamous pairs during breeding, but reliable visual sexing is not described.

Spawning Behavior & Trigger

Butterflyfish are pelagic spawners: paired fish release many buoyant eggs into the water, which become part of the plankton and float with the currents until hatching (Wikipedia). Chaetodon lunula forms distinct breeding pairs (FishBase). This open-water release of eggs cannot be reproduced or captured in an aquarium.

Egg & Fry Care

The larvae pass through the distinctive tholichthys stage characteristic of butterflyfish, in which the post-larval body is covered in large bony plates that are lost as the fish matures (Wikipedia). This long planktonic larval phase, with minute first-stage larvae drifting in open water, places butterflyfish among the most challenging marine fish to rear, and no home protocol exists for this species.

Common Challenges

The combination of broadcast pelagic eggs, a prolonged drifting larval period, and the tholichthys stage means that breeding Chaetodon lunula is beyond home aquaria. Keeping a healthy bonded pair is feasible, but reproduction to settlement is not.