''Trachurus delagoa'', the African scad, is a species of

jack mackerel Jack mackerels or saurels are marine fish in the genus ''Trachurus'' of the family Carangidae. The name of the genus derives from the Greek words ''trachys'' ("rough") and ''oura'' ("tail"). Some species, such as ''T. murphyi'', are harvested in ...

from the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Carangidae The Carangidae are a family of ray-finned fish which includes the jacks, pompanos, jack mackerels, runners, and scads. It is the largest of the six families included within the order Carangiformes. Some authorities classify it as the only family ...

which is found in the south western Indian Ocean.

Description

''Trachurus delagoa'' has an elongate body which is slightly compressed and has the upper and lower profiles roughly the same. The eye is moderately large and has a well-developed adipose eyelid which normally covers almost all of the eye apart from a vertical oval with the pupil in the centre. It has a reasonably wide upper jaw which extends to underneath the forward anterior edge of the eye. The mouth is equipped with small teeth, having a single row in each jaw. It has two separate

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

s, the first having 8 spines with the second having a single spine and 28 to 32 soft rays. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has 2 detached spines to its front followed by a single spine and 24 to 28 soft rays. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

s are as long or longer than the length of the head. The scales in the lateral line and large and form scutes. It has a black spot on the upper margin of the operculum, the upper part of the body is dark blue and the flanks and belly are silvery. The anal and pectoral fins are pale yellow in colour, the

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

is grey and the pelvic fins are white or unpigmented. It grows to a maximum

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

of .

Distribution

''Trachurus delagoa'' occurs in the south-western Indian Ocean off the eastern costa of Africa from

Eastern Cape Province The Eastern Cape is one of the provinces of South Africa. Its capital is Bhisho, but its two largest cities are East London and Gqeberha. The second largest province in the country (at 168,966 km2) after Northern Cape, it was formed in 199 ...

to southern Mozambique. It is also found off southern Madagascar and the

Walters Shoals The Walters Shoals is a group of submerged mountains off the coast of Madagascar. The shoals are south of Cape Sainte Marie - Madagascar and east of Richards Bay at the Africa Africa is the world's second-largest and second-most po ...

Habitat and biology

''Trachurus delagoa'' is largely demersal and occurs in areas of the

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an island ...

where there is a sandy substrate. It ranges in depth from the shoreline to around . It spends the day in the depths and undertakes a vertical migration at night to feed near the surface. Its prey is made up largely of smaller fish and crustaceans. It is a social species which forms schools.

Fisheries

African scads are largely fished for with bottown trawls and with hook and line. In

KwaZulu Natal KwaZulu-Natal (, also referred to as KZN and known as "the garden province") is a province of South Africa that was created in 1994 when the Zulu bantustan of KwaZulu ("Place of the Zulu" in Zulu) and Natal Province were merged. It is locat ...

it is fished for on a small scale by fishermen on paddleboards or kayaks.

References

{{taxonbar, from=Q2272654 Trachurus delagoa Marine fauna of Southern Africa Fish of Madagascar Fish described in 1970