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butterflyfish 
INDO-PACIFIC Coral Reef

The beautiful and diverse butterflyfish...

Family Chaetodontidae, 'Butterflyfish'

Butterflyfish are medium sized fish that are extremely laterally compressed; that is, they have the shape of plate. They are usually dominated by black and yellow colours, but there are many variations. Butterflyfish are usually found in pairs.

This is my favourite group of fish! There are many species to identify, but all are distinct and relatively easy to identify...  

Forcipiger spp.

(Aitutaki, Fiji)

Forcipiger flavissimus, 'Long-nosed Butterflyfish'. There is another species called the 'Very Long-nosed Butterflyfish', which has a longer 'nose'. 

Chelmon spp. 'Coralfish'

Butterflyfish with silver bodies and thin orange bars, and long beaks. There are three species, with two of those being endemic to Australian waters. Feed on various invertebrates. 

(I think I might have taken this shot in an aquarium)

Chelmon rostratus, 'Copperband (Coralfish) Butterflyfish'. Distinguished by false eyespot on dorsal fin (even if faded as in image above). The more widespread of the Coralfish.

Heniochus spp.

These butterflyfish have either a very long thin dorsal fin (which makes them look like a Moorish Idol), or dorsal fins that look like 'torn paper'.

(Solomon islands)

Heniochus chrysostomus, 'Three-banded Bannerfish'. 'Torn paper' dorsal fin. Orange snout.

(Aquarium)

Heniochus acuminatus, 'Long-finned bannerfish'. Looks similar to Heniochus diphreutes, but the above pictured species has a slightly longer beak. Feeds on zooplankton in open water around coral reefs, distributed widely around Indo-Pacific.

Chaetodon spp.

This large genus has been divided into various groups...

Chaetodon - Lepidochaetodon group - subgenus Exornator

(Aitutaki, Fiji)

Chaetodon citrinellus, 'Speckled Butterflyfish'.

Chaetodon pelwensis, ‘Dot Dash Butterflyfish’, ‘Sunset Butterflyfish’. Found around Australia and the western Pacific.

(Niue)

Chaetodon quadrimaculatus, 'Four-spot Butterflyfish'. Found on tropical coral reefs in central and northern Pacific.

Chaetodon - Lepidochaetodon group - subgenus Lepidochaetodon

(to be inserted) Chaetodon unimaculatus, ‘Teardrop Butterflyfish’.

(Solomon Islands)

Chaetodon kleinii, ‘Black-lipped Butterflyfish’, ‘Sunburst Butterflyfish’. Widespread, from East Africa, all the way to the Galapagos.

Chaetodon - Megaprotodon group - Subgenus Citharoedus

(Jaco, East Timor)

Chaetodon meyersi, ‘Meyer’s Butterflyfish’, 'Scrawled Butterflyfish'. Very widespread throughout coral reefs of the tropical Indo-Pacific, with vagrants even reaching Central America.

(Niue)

Chaetodon reticulatus, 'Reticulated Butterflyfish', 'Mailed Butterflyfish'.

Chaetodon - Megaprotodon group - Subgenus Corallochaetodon

(Miyako Island, Japan)

Chaetodon lunulatus, 'Oval/Pacific Redfin Butterflyfish'.

Chaetodon - Megaprotodon group - Subgenus Discochaetodon

(Misool, Indonesia)

Chaetodon octofasciatus, 'Eightband Butterflyfish'.

Chaetodon rainfordi, ‘Gold-barred Butterflyfish’. Mostly found around Australasia.

Chaetodon - Megaprotodon group – Subgenus Megaprotodon

(Borneo)

Chaetodon trifascialis, ‘Chevron Butterflyfish’, 'V-lined Butterflyfish'.

Chaetodon - Megaprotodon group - Subgenus Tetrachaetodon

(Pink Beach, Komodo, Indonesia)

Chaetodon bennetti, 'Eclipse/Blue-lashed Butterflyfish'.

Chaetodon - Rabdophorus group

(Alphonsa, Seychelles)

Chaetodon xanthocephalus, 'Yellow-headed Butterflyfish'.

Chaetodon auriga, ‘Threadfin Butterflyfish’. As suggested by common name, thin filament from dorsal fin. Very widespread, from east Africa to Polynesia.

(To be inserted) Chaetodon vagabundus, ‘Vagabond Butterflyfish’.

(Miyako, Japan)

Chaetodon rafflesii, 'Lattice Butterflyfish'. Looks like a pineapple!

(Miyako, Japan)

Chaetodon lineolatus, 'Lined Butterflyfish'. One of the larger butterflyfish. Found on tropical coral reefs, from east coast of Africa across to Philippines, but is not particularly common.

(Borneo)

Chaetodon adiergastos, ‘Panda Butterflyfish’, (‘Philippine Butterflyfish’). Found around Asia & Australia.

Chaetodon flavirostris, ‘Black Butterflyfish’, ‘Dusky Butterflyfish’. Found in southern tropical Pacific, from the Great Barrier Reef, east to the Pitcairn Islands.

(to be inserted) Chaetodon collare, ‘White-collared/Red-tailed Butterflyfish’.

(Pink Beach, Indonesia)

Chaetodon melannotus, ‘Blackback Butterflyfish’. Found around tropical coral reefs from east Africa and east to Samoa.

Chaetodon ulietensis, ‘Pacific Double-saddle Butterflyfish’. Found around coral reefs in tropical Pacific Ocean. There is a similar and equivalent species in the Indian Ocean.

Chaetodon ephippium, '(Black) Saddled Butterflyfish'. One of the most distinct and largest of all butterflyfish. Found on coral reefs in from central Indian Ocean across to Polynesia.

Updates
My first trip after the virus is as Expedition leader in Tasmania with Coral Expeditions, followed by my role as biologist guest lecturer on the Great Barrier Reef. If you can't go travelling until everything settles down, then until then, here I am doing online guided walks for Noble Caledonia and online lectures for Silversea.