Giant Trevally

The giant trevally (Caranx ignobilis), also known as the giant jack, is a large fish from the jack family, characterized by outstanding size and strength. It is one of the largest species of trevally, reaching more than 1.5 m in length and weighing over 80 kg. The giant trevally stands out not only for its size but also for its strength, as well as the manifestation of social behavior that changes throughout its life.

The body shape is elongated, relatively high, slightly compressed laterally. The skin is covered with small cycloid scales, except for the area of the pectoral fins. The head has a rounded snout, the length of the upper jaw extends to a vertical line passing through the posterior edge of the eye. The eyes are medium-sized, with a well-developed adipose eyelid. The mouth has an abundant row of large fangs in the upper jaw and one row of teeth in the lower. The gill arches contain 6-9 gill rakers above and 16-19 below. There are two dorsal fins with eight and one hard ray respectively, as well as an anal fin with one spiny and 16-17 soft rays. The pectoral fins are elongated and have a sickle shape. The lateral line forms a high arch in the anterior part of the body and runs straight to the caudal peduncle. The caudal fin has a sickle shape.

Body coloration varies from greenish to bluish or bluish-black above and from silvery-white to yellowish or golden below. There is one oval black spot on the gill cover and the lower part of the pectoral fins, and the anal fin lobes are completely colored yellow. Juveniles usually have five dark stripes along the sides of the body.

The maximum body length is more than 1.5 m (up to 170 cm), and the maximum weight reaches over 80 kg.

It can be argued that the trevally represents one of the few prehistoric creatures that have survived with minimal changes since the era of dinosaurs. Research by ichthyologists indicates that the species formed about 60 million years ago and has practically not undergone evolutionary changes.

Paleontologists have discovered bone remains of trevally in Cretaceous deposits at depths up to 8 meters, corresponding to the Cretaceous period. The first ossified remains were discovered in 1801, and since then such finds have become frequent. The description of the fish in its current form was presented in the mid-19th century and entered into the works of Carl Linnaeus. Despite the 200 years that have passed, the appearance and characteristics of the fish have remained practically unchanged, making its description relevant even today.