Distribution

1. Mediterranean
2. Atlantic from Morocco to Norway, North Sea, Mediterranean, Black Sea 
3. Mediterranean, African Atlantic Coast from Morocco to Senegal 
4. Eastern Atlantic coast from Scotland to West Africa, Mediterranean

Fig. 4.30  Trachinus draco

Biology

Marine, bottom-dwelling fishes with large head. Eyes and mouth directed upwards, body tapered toward the rear. T. aranaeus as the largest species barely longer than 50 cm.

T. draco lives in deeper water; the other species more often in shallow water. They prefer a sandy or muddy substrate, which they can dig themselves into, apart from the topmost part of their head, and wait for prey. There are 5–8 rays in the anterior dorsal fin, as well as 1 on each of the gill covers, which have grooves on both sides and are equipped with venom glands. Envenoming generally occurs when victims are wading or swimming in shallow water, where the buried Weeverfishes are easily startled and can use their gill spines to aim defensive stings at their victim.

Risk

Most bathing accidents involve the Lesser weeverfish (T. vipera), which is often found in very shallow water. T. draco, the species that prefers deeper water zones, can cause envenoming in fishermen if they are careless when removing the fish from their nets.
As Weeverfishes are prized edible fish, it is imperative that care be taken when preparing these fish. The venomous spines are not always removed before the fish are sold.
In the Mediterranean weeverfishes cause many accidents every year. In most cases envenoming is limited to local effects, but it is believed to take a severe course in rare cases. Isolated fatalities have been reported. It is possible that secondary bacterial infections were responsible for these deaths, rather than systemic effects of the venom. In more recent times there have been no known fatalities.

Literature (biological)

Cain 1983, Gonzaga 1985, Halstead 1988, Riedl 1983