Family : Chaetodontidae
Text © Giuseppe Mazza
English translation by Mario Beltramini
The Lined butterflyfish (Chaetodon lineolatus Cuvier, 1831) is the greatest in its genus. It belongs to the class of Actinopterygii, the ray-finned fishes, to the order of Perciformes and to the family of Chaetodontidae.
The name of the genus Chaetodon comes from the Greek “χαίτη” (khaite) = hair and “ὀδούς” (odous) = tooth, due to the “bristle-shaped teeth”.
The name of the species lineolatus means in Latin “with small lines”, with reference to its thin vertical stripes.
It has a very vast distribution in the tropical waters of the Indo-Pacific.
We find it from South Africa, Madagascar and the Seychelles up to the Red Sea ad the Arabic Sea, and the to the Maldives, Sri Lanka, Thailand, Australia, Indone- sia, New Guinea, New Caledonia, Philippines, China and Taiwan up to southern Japan. Eastwards, it reaches the Fiji, Tonga and Hawaii islands, southwards, Norfolk and Lord Howe islands.
It lives in the coral formations, going down even to great depths for a butterflyfish, well beyond the 170 m.
The Lined butterflyfish can reach the 30 cm and is the greatest member of the genus Chaetodon.
The body is flat, more or less oval, with elongated snout and an unusual mouth with big lips.
The dorsal fin has 12 spiny rays and 24-27 soft; the anal has 3 spiny rays and 19-22 soft; the ventral 1 spine and 5 soft rays; the pectoral ones are unarmed with 16-18 rays; the caudal is more or less blunt.
Most of the body is white with some vertical black traits stopping in the ventral zone. The back and the adjacent fins are of a nice bright yellow colour, crossed by a large curved black band more or less of the same length as the vertical one, ramified up, hiding the eye. Before the translucent zone, the tail exhibits a dark yellowish pattern.
The Lined butterflyfish nourishes more of benthic invertebrates than of polyps of madrepores. In its menu enter the splendid Spirobranchus, sea ane- mones belonging to the order of the Zoanthidea, the clams and even some seaweed.
It is often sighted paired, but it can move around alone or in small schools. The eggs are pelagic and the juveniles have a lifespan of 50 years. The populations can double in less than 15 months, but aquaria trade apart, the future of the species is related to that of the reefs. The fishing vulnerability index is currently low and marks 20 on a scale of 100.
Anisochaetodon lineolatus Cuvier, 1831; Chaetodon lunatus Cuvier, 1831; Chaetodon tallii Bleeker, 1854; Tetragonoptrus lineolatus Cuvier, 1831.