---
title: Diagonal Butterflyfish (Chaetodon fasciatus)
scientific_name: Chaetodon fasciatus
common_name: Diagonal Butterflyfish
taxon: Butterflyfishes
conservation_status: LC - Least Concern
published: 2023-12-22T22:41:22.161Z
updated: 2026-08-20T17:09:44.903Z
tags: Diagonal Butterflyfish, Chaetodon fasciatus, Butterflyfishes, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/fishes/bony-fishes/butterflyfishes/diagonal-butterflyfish
---

# Diagonal Butterflyfish (*Chaetodon fasciatus*)

## Quick facts

- **Group:** Butterflyfishes (*Chaetodontidae*)
- **Size:** up to 25 cm
- **Depth:** 1-25 m
- **Diet:** Corallivore
- **Activity:** Diurnal
- **Rarity:** Common
- **Habitat:** Coral-rich reef slopes and lagoons
- **Endemic:** Endemic to the Red Sea
- **Conservation status:** LC - Least Concern

## How to recognise it

- yellow body crossed by dark diagonal stripes
- black bar through the eye, white band behind it
- tail base plain yellow - no black blotch

A deep-bodied yellow butterflyfish crossed by a series of dark, slightly diagonal stripes running up and back across the flanks. A black bar drops through the eye, bordered behind by a clean white band, and a black band runs along the base of the dorsal fin and around the rear of the body. The upper edge of the dorsal fin is orange-red, and the tail base stays plain yellow. Length reaches about 25 cm (10 in), large for the family.

The species is endemic here, one of the fish a diver can see on nearly every Red Sea reef and nowhere else on earth. Adults pair for life and patrol coral-rich slopes and lagoons from just below the surface to about 25 m (80 ft), feeding through the day on coral polyps, small invertebrates and algae. Pairs stay within sight of one another and will circle back if separated. At night the fish retreat into the reef and take on a dull blotched pattern that makes them hard to recognize by torchlight. Dive guides and older checklists often call it the raccoon butterflyfish, borrowing the name of a similar Indo-Pacific species, Chaetodon lunula, which does not reach this sea - the black blotch on the tail base of that one separates the two at a glance.

## Also known as

- **English:** diagonal butterflyfish, Red Sea Butter Flyfish, striped butterflyfish
- **Arabic:** Moscht
- **Hebrew:** פרפרון לבן-מצח
- **French:** Poisson-papillon raton laveur de mer Rouge, Papillon rayé
- **Italian:** Pesce farfalla mascherato del Mar Rosso, Pesce farfalla procione del Mar Rosso
- **German:** Tabak-Falterfisch
- **Spanish:** Pez Mariposa Mapache del Mar Rojo, Pez mariposa diagonal
- **Portuguese:** Peixe-borboleta-diagonal
- **Dutch:** Masker Koraalvlinder
- **Czech:** klipka páskovaná
- **Russian:** Диагональная рыба-бабочка
- **CA:** Peix papallona mapache del Mar Roja
- **DA:** Rødehavsfanefisk

## Scientific synonyms

- *Chaetodon flavus* Bloch & Schneider, 1801
- *Rabdophorus linophora fasciatus* (Forsskål, 1775)

## Range

Djibouti, Eritrea, Kenya, Red Sea

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*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/fishes/bony-fishes/butterflyfishes/diagonal-butterflyfish)*
*Updated: August 20, 2026*