A new study of the Cano toadfish, Thalassophryne maculosa, has shown that its venom also contains potent biotoxins which cause lesions when humans step on it.
A team of scientists from Universidad de Oriente, Venezuela, used molecular techniques to determine what was in the venom of the batrachoidid toadfish that were responsible for the extreme reaction its stings cause in humans.
Unlike most venomous fishes, the stings from this Venezuelan batrachoidid cause severe pain, dizziness, edema, fever and tissue necrosis and wounds may take weeks, or even months, to recover.
The study showed that, although lacking in the phospholipase A(2) activity seen in other venomous fish, the venom worked both proteolytically and myotoxically, suggesting that it contains some additional biotoxins responsible for causing the severe lesions.
The venomous fish, which is a close relative of the freshwater Prehistoric monster fish, Thalassophryne amazonica, wounds hundreds of people in Venezuela every year when they step on it, or accidentally get jabbed by its spines when it is caught in their nets.
For more information see the paper: Sosa-Rosales JI, Piran-Soares AA, Farsky SH, Takehara HA, Lima C, Lopes-Ferreira M (2005) - Important biological activities induced by Thalassophryne maculosa fish venom. Toxicon. 2005 Feb ; 45(2): 155-161.