Dot-and-dash Butterflyfish

Chaetodon pelwensis has a dusky yellow body with diagonal stripes across the body and black-margined gold vertical bar through the eye. There is a black spot on the head. The stripes break up into spots towards the head and on the lower flanks. The margins of the fins are bright yellow and the base of the caudal fin is bright orange. The dorsal fin has 13–14 spines and 22–25 soft rays while the anal fin has 3 spines and 17–18 soft rays. It attains a maximum total length of 12.5 centimetres (4.9 in).

Chaetodon pelewensis is found across the southern Pacific Ocean from Papua New Guinea to the Tuamotu Archipelago. This species is abundant on the Great Barrier Reef and in the Coral Sea. In Australia it extends as far south as central New South Wales and Lord Howe Island.

Chaetodon pelewensis was first formally described in 1868 by the Austrian ichthyologist Rudolf Kner (1810–1869) with the type locality given as Palau in the Western Pacific, Pelew Inseln in German, in error when the correct type locality is probably the Society Islands. The specific name reflects the erroneous designation of the type locality. This species is placed in the subgenus Exornator, if the genus Chaetodon is split up, Exornator might become a subgenus of Lepidochaetodon.