Cantherhines longicaudusis commonly referred to as Squaretail Filefish. Difficulty in the aquarium: There are no reports available yet that this animal has already been kept in captivity successfully. Toxicity: Toxic hazard unknown.
Cantherhines longicaudus is immediately noticeable for its yellow head and body, with hints of four rows of faint dark spots and blotches on the body.
A dark brown band extending from the edge of the eye socket to the upper base of the pectoral fins is conspicuous, as are two faint bands crossing the eyes, a broad anterior one connecting the anterior edges of the eye sockets and a narrow posterior one at the origin of the first dorsal spine.
There are five faint, large, dark spots on the ventral side, the first on the chin and the last just anterior to the posterior part of the pelvis.
The caudal fin rays of the filefish are dull yellow, and the membranes are brownish yellow.
Etymology: The species name "longicaudus" comes from Latin, "longus" meaning "long" and "cauda" meaning "tail", in reference to the long caudal fin of this species.