Description:

Dorsal spines: 13-14; Dorsal rays: 20-22; Anal spines: 3; Anal rays: 18-21.

Small, oval shaped, laterally compressed fish. Angular snout with terminal mouth.
  
Colour. A complex colour pattern with many fine details (see photos). In summary, however: base colour pale orange shading to bluish posteriorly. Blue grey stripes run the 
length of the body from rear of the opercle, the fifth line down bearing a black streak in its posterior third. A yellow margined black band runs down the head through the 
eye to the “throat”. A white and black band runs adjacent to it posteriorly. The snout is black with tip and mouth a brownish orange. The anal, caudal and posterior dorsal 
fin bases exhibit a yellow-margined black band. The anal fin has an outer yellow edge. The caudal peduncle is orange and the distal portion of the caudal fin is transparent. 
The posterior portion of the dorsal fin exhibits a white band with a narrow black line running though it and a narrow black edge followed by an outer orange margin. Pectoral 
fin is transparent. Pelvic fins are pale orange. 

Maturity: Lm unknown. Range Unknown. Max Length: 15cm TL. Commonly to 12cm TL.

Inhabits coral rich lagoons and sheltered portions of reefs (depth 2-30m, usually 2-20m). Swim in pairs. Oviparous, Distinct pairing in breeding. Small juveniles secretive 
in corals. Obligate corallivore feeds exclusively on coral polyps, particularly of the Pocillopora type.

This species is not protected or subject to fishery regulations. It is caught in the fish trap fishery and also in nets, but is an uncommon component of the landed catch, 
as it is typically released by fishers when caught

A 30% decline in population have been documented in Seychelles following the 1997/98 coral bleaching event.  

Bray, D.J. Chaetodon trifasciatus in Fishes of Australia, http://fishesofaustralia.net.au/home/species/4835 (16/06/19). 
Froese, R. & D. Pauly. (Eds.) (2019). FishBase. https://www.fishbase.se/summary/Chaetodon-trifasciatus (16/06/19).
Graham, N.A.J. et al. (2007). Lag effects in the impacts of mass coral bleaching on coral reef fish, fisheries, and ecosystems. Conservation Biology 21(5): 1291-1300.
Pyle, R. et al. (2010). Chaetodon trifasciatus. The IUCN Red List 2010: http://dx.doi.org/10.2305/IUCN.UK.2010-4.RLTS.T165673A6087793.en. (16/06/19).

Nevill, J.E.G. (2019). Chaetodon trifasciatus, Melon butterflyfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/chaetodon-trifasciatus-park-1797/ (edited 30/06/22).