Striated surgeonfishCtenochaetus striatus

Category
  • Fringing Reef
Tags
  • Surgeonfish
  • Lagoon coral patches
  • Fauna

Description

Ctenochaetus striatus belongs to the order of Perciformes and family of Acanthuridae (Surgeonfish, Tangs and Unicornfish). Common names include Striped Bristle-tooth, Bristle-toothed surgeonfish, Lined bristle-tooth, Orange-dotted bristle-tooth and Striated surgeonfish. Their body has an overall dark olive-brown colour. Orange spots are present on the head and wavy blue lines across the body[1]. The pectoral fin is yellowish, while the caudal and ventral fins are brown, and the anterior caudal fin is pale. The caudal peduncle has sharp sides with erect thorns that point forward. Minute scales are present. The teeth are movable, thin and curve inwards. It has a total of 8 dorsal spines, 27 to 31 dorsal soft rays, 3 anal spines and 24 to 28 anal soft rays. This species can reach a maximum of 26cm. The juveniles possess 8 to 12 pale stripes that incline down and back on the body[2].

 

[1] Tebbett, Goatley, and Bellwood, ‘Clarifying Functional Roles’.

[2] ‘Ctenochaetus Striatus Summary Page’.

Habitat and ecology

This species is present across the Indo-Pacific region, from the Red Sea and the coast of East Africa to Pitcairn Island, and French Polynesia. It is spread northwards to the Ryukyu and Ogasawara Islands, Japan and southwards to Elizabeth/Middleton Reefs and Rapa. It is found in a range of habitats, from lagoons to ocean reefs. Their diet consists of dead material found in sand or other substrates, surface film of blue-green algae and other small organisms.

Spawning begins near the full moon and has been recorded in Tahiti. Large groups are form and the fish remain motionless for 1 to 3 hours. Their body colour changes to pale grey. Four to five fish out of the group  swim upwards and around the group, releasing milt and eggs. They then return to their position. Another set of four to five fish repeat the act and this continues until spawning is complete.

 

Conservation and management

According to the IUCN Red list, this species is categorized as being of ‘Least Concern’ as it is common and widespread. It is collected in parts of its range but no impacts on global population have been recorded. No conservation measures are in place for this species. However, it is present in many MPAs. Monitoring of this fish species is recommended, especially in areas where it is exploited commercially[1].

 

 


[1] ‘Ctenochaetus Striatus Summary Page’.

Did you know?

This species feeds by whisking sand or hard substrates such as rock surfaces with its teeth and suctioning any dead material.