Trachinus draco

Trachinus draco is commonly known as greater weever. It is a fish belonging to the class Actinopterygii, the order perciformes and the family Trachinidae, which inhabits sandy and/or muddy bottoms from shallow waters up to 200 meters deep, although between 20 and 50 meters is where they are most abundant. Its distribution is wide in the eastern Atlantic Ocean, from the coasts of Morocco and Mauritania, but also present in the Canary Islands, Madeira, to the coasts of Norway. It is also present in the Mediterranean Sea and the Black Sea.

Trachinus draco can reach 40 cm in length. Its body is elongated and flattened laterally, with a large head with small eyes in an elevated position and a large mouth facing upwards. It has anterodorsal spines located on the head, as well as large spines on the operculum. It has two dorsal fins, the first is short and has 5-7 spines, while the second dorsal fin is longer and consists of 29-32 soft rays. The anal fin is formed by 2 spines and 27-34 soft rays and its length is similar to the second dorsal fin. As a distinctive feature of this fish family, the spiny rays of the dorsal fin, as well as the spines of the operculum, are connected to toxin-secreting glands. These spines are protected by a thin membranous layer.

As for the coloration of Trachinus draco, dorsally they are green with oblique greenish-brown lines. The sides and ventral area is light yellow. This species, due to its coloration, does not usually present confusion in identification compared to the other three members of the family that are present in the Mediterranean.

As expected from its anatomical characteristics, Trachinus draco lives buried in the sand, leaving only its head uncovered. This is why they can pose a danger especially for bathers, since this species does not flee in the presence of bathers, but rather bristles its spines, and if the bather steps on the specimen, the membrane covering the spines tears on contact, releasing the toxins. The sting causes intense pain and inflammation, which spreads to adjacent tissues. The swelling can last for several days.

Trachinus draco migrate to deeper waters during the winter months, while in the summer months they are found in shallower waters. The diet of this species is varied, and we find among its prey small fish and invertebrates.


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