The oval butterflyfish and the black-tailed butterflyfish resemble C. trifasciatus in coloration.
The former has a less conspicuous back patch below the dorsal fin and a mainly dark anal fin, while the latter has black caudal and anal fins.

Melon, black-tailed and oval butterflyfishes and probably also the somewhat aberrant Arabian butterflyfish (C. melapterus) make up the subgenus Corallochaetodon, of which C. trifasciatus is the type species.
They are probably quite close to the subgenus called "Citharoedus" (that name is a junior homonym of a mollusc genus), which contains for example the Scrawled butterflyfish (C. meyeri).
Like that group, they might be separated in Megaprotodon if the genus Chaetodon is split up.
The oval butterflyfish and the black-tailed butterflyfish resemble C. trifasciatus in coloration. The former has a less conspicuous back patch below the dorsal fin and a mainly dark anal fin, while the latter has black caudal and anal fins.
Melon, black-tailed and oval butterflyfishes and probably also the somewhat aberrant Arabian butterflyfish (C. melapterus) make up the subgenus Corallochaetodon, of which C. trifasciatus is the type species. They are probably quite close to the subgenus called "Citharoedus" (that name is a junior homonym of a mollusc genus), which contains for example the Scrawled butterflyfish (C. meyeri). Like that group, they might be separated in Megaprotodon if the genus Chaetodon is split up.
Melon butterflyfish