About Epinephelus cyanopodus (Richardson, 1846)
Body Shape
Epinephelus cyanopodus has a compressed body, with a standard length that is 2.4 to 2.7 times its body depth. It has a steep dorsal profile on the head and a noticeably convex area between the eyes.
Preopercle Features
Its preopercle does not have a sharp angle, and the edge of the preopercle has fine serrations that are slightly enlarged at the angle. The gill cover has inconspicuous spines and a straight upper edge.
Fin Structure
The dorsal fin has 11 spines and 16-17 soft rays, while the anal fin has 3 spines and 8 soft rays. The membrane between the spines in the spiny section of the dorsal fin is either not incised or only slightly incised.
Lateral Line Scales
There are 63 to 75 scales along the lateral line.
Adult Coloration
Adults of this species are overall greyish, covered in small irregular dark dots, with a smaller number of larger black spots.
Juvenile Coloration
Juveniles are yellowish, and become more greyish-blue as they mature. When juveniles reach 15–20 cm (5.9–7.9 in) in length, only their fins remain yellowish, and this yellow fin color fades as the fish ages further.
Size and Weight
This species can reach a maximum total length of 122 cm (48 in) and a maximum weight of 17.3 kg (38 lb).
General Distribution
Epinephelus cyanopodus occurs in the Western Pacific Ocean. Its range extends from the South China Sea and the Gulf of Thailand east to the Marshall Islands and Fiji, north to southern Japan, and south to eastern Australia and the Tasman Sea.
Australian Distribution
In Australia, it is found along the Great Barrier Reef, and along the coast from northern Queensland to Sydney.
Habitat Preferences
This grouper is most often found near isolated coral heads in lagoons or bays, though specimens have also been collected from outer reefs. It is not a cryptic species, and is normally encountered in the water column several meters above the seabed.
Catch Pattern
It is frequently caught during the night.
Diet
It is a predatory species that feeds mainly on fish and sand-dwelling crustaceans such as snake eels and box crabs.
Spawning Behavior
During the breeding season, this species forms spawning aggregations that are often mixed with other grouper species including Epinephelus polyphekadion and Epinephelus fuscoguttatus. The overall biology of this species remains poorly understood.
Depth Range
It inhabits waters at depths ranging from 2 to 150 metres (6.6 to 492.1 ft).