Eastern Triangle Butterflyfish

Not to be confused with the Triangle Butterflyfish (C. triangulum) and the Triangulate Butterflyfish (C. trifascialis).

Eastern Triangle Butterflyfish
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Chaetodontidae
Genus:	Chaetodon (but see text)
Subgenus:	Gonochaetodon
Species:	C. (G.) baronessa
Binomial name
Chaetodon (Gonochaetodon) baronessa Cuvier, 1829

The Eastern Triangle Butterflyfish, Chaetodon baronessa, is a species of butterflyfish (family Chaetodontidae). It is found in the Indo-West Pacific region from the Cocos-Keeling Islands and Indonesia in the eastern Indian Ocean to Fiji and Tonga, north to southern Japan, south to New Caledonia and New South Wales in Australia.^[1]

It grows to a maximum of 16 cm long. The body has a pattern of alternating cream and grey-brown to purple chevron-shaped bars. There are three dark bars on the head, including one running across the eye.^[1]

The Triangle Butterflyfish (C. triangulum) is its western sister species, replacing C. baronessa in the Indian Ocean. The triangle butterflyfishes and the Hooded Butterflyfish (C. larvatus) form the subgenus Gonochaetodon. If Chaetodon is split up as some researchers propose, this group might go into Megaprotodon as other high-backed and square-bodied species, but its exact relationships are still not well known.^[2]

The Eastern Triangle Butterflyfish is found in seaward and lagoon coral reefs. They usually swim around in pairs and are territorial. This species feeds exclusively on the polyps of the tubular Acropora corals.^[1]

Footnotes

1. ^ ^{a b c} FishBase (2008)
2. ^ Fessler & Westneat (2007), Hsu et al. (2007)

References

• Fessler, Jennifer L. & Westneat, Mark W. (2007): Molecular phylogenetics of the butterflyfishes (Chaetodontidae): Taxonomy and biogeography of a global coral reef fish family. Mol. Phylogenet. Evol. 45(1): 50–68. doi:10.1016/j.ympev.2007.05.018 (HTML abstract)
• FishBase (2008): Chaetodon baronessa. Version of 2008-JUL-24. Retrieved 2008-SEP-01.
• Hsu, Kui-Ching; Chen, Jeng-Ping & Shao, Kwang-Tsao (2007): Molecular phylogeny of Chaetodon (Teleostei: Chaetodontidae) in the Indo-West Pacific: evolution in geminate species pairs and species groups. Raffles Bulletin of Zoology Supplement 14: 77-86. PDF fulltext