Latin name

Dussumieria acuta

Other name

Common sprat, dwarf round herring, rainbow herring, and sharpnosed sprat.

Identification

The body of the rainbow sardine is prominent, slightly flattened at the sides and covered with large cycloid scales; body length is 3.4-4.5 times less than length. The belly is rounded, without a keel (there is a W-shaped keel scale at the base of the pelvic fins). The length of the small head is 4 times less than the length of the body and 3.6 times more than the length of the snout. The length of the upper jaw of the large mouth is about 80% of the length of the snout, the jaw stopping just short of the edge of the eye socket. There is a thin fatty eyelid. 

Features of fish fins

The dorsal fin is closer to the caudal fin than to the snout. The anal fin is small. The pelvic fins are opposite the dorsal fin. The caudal fin is bifurcated. 

The dorsal fin has 18-20 rays; anal fin 14-18; pectoral fin 14-15; pelvic fin 8.

Fish colouring

The coloration of the dorsal surface of these fish is gray-brown, head and sides are tan, belly is silver, dorsal and caudal fins are tan, anal and pelvic fins are whitish.

Distribution

Widespread in the northern Indian Ocean from Somalia to Java and Sumatra, along the coast of Hindustan; and in the western Pacific off Kalimantan, Sulawesi, and the Philippines. 

Habitat

This marine pelagic fish is found in coastal waters with water temperatures of 28°C.

Size

The maximum body length of fish of this species is 20 cm.

Behavior

These mobile fish make short migrations within their habitat. Rainbow sardine do not form benthic schools and remain dispersed in the water column. 

Food and feeding habits

This species feeds on zooplankton.

Reproduction

Off the coast of Arabia, rainbow sardine spawning begins in May and ends in October. Peak spawning occurs between May and July. During spawning, spotted sardine do not approach the shore. Females hatch up to three portions of eggs per season. In the first portion of about 68 thousand eggs, in the last - 48 thousand eggs. Fish reach sexual maturity at the age of about 2 years with a body length of 13-15 cm. Life expectancy is estimated at 4-5 years. The spawning stock is dominated by fish 2-3 years old and 14-17 cm in size.

Fishing

The species is of highly commercial interest. They are fished locally, for example in the waters of Tuticorin and Fiji. They are fished with trawls and purse seines. 

Relationship with a person

Harmless. This fish is used to make canned food.