Scientific Name
Ctenochaetus binotatus

Common Name
Twospot surgeonfish

Biology
Dorsal spines (total): 8; Dorsal soft rays (total): 24-27; Anal spines: 3; Anal soft rays: 22 - 25. Prominent black spot at the rear base of dorsal and anal fins; adults with a bluish ring around the eye (Ref 1602). Dorsal and anal fins dark brown. Caudal fin brown in adults, yellow in young. Edge of lips smooth. Upper teeth usually with 5 denticulations (not including tip). Anterior gill rakers 23-29 (Ref 42056).

Classification

Classified By

Randall, 1955

Class

Ray-finned fishes (Actinopterygii)

Order

Perch-like fish (Perciformes)

Family

Surgeonfishes, tangs, unicornfishes (Acanthuridae)

Distribution

Region

Indo-Pacific

Distribution

Indo-Pacific: East Africa to the Tuamoto Islands, north to southern Japan, south to central New South Wales (Australia) and New Caledonia. Not known from the Red Sea, Gulf of Oman, the Gulf, the Hawaiian Islands, Marquesas, Rapa, Pitcairn Islands, and Easter Island.

Range

24°N - 34°S, 29°E - 155°E

Environment

Climate

Tropical

Water Temperature From

24 °C

Water Temperature To

26 °C

Depth From - meters

8 m

Depth To - meters

53 m

Zone

reef-associated

Environment

Marine; reef-associated; depth range 8 - 53 m (Ref. 1602), usually 10 - 50 m (Ref. 27115)

Trophic Level

2 s.e. 0.00 Based on food items.

Occurs in Marine / Salt water

True

Occurs in Brackish water

False

Occurs in Fresh Water

False

Occurs on Reefs

True

Is kept in Aquariums

True

Physical Size and Genetics

Maximum Length

22.0 cm

Common Length

Unknown cm

Phylogenetic Diversity Index

PD50 = 0.5020 many relatives (e.g. carps) 0.5 - 2.0 few relatives (e.g. lungfishes)

Human Uses and Population

Human Uses

Aquarium: commercial

Vulnerability

Low vulnerability (24 of 100)

Resilience

High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.)

Threat To Humans

Other (Ref. 1602)

IUCN Red List Status

Not Evaluated