Most venomous scorpion
Fat-tailed scorpions
Not Applicable ()

The most venomous scorpions are the fat-tailed scorpions belonging to the genus Androctonus. Several of these species rival each other in terms of the strength of their venom. The Tunisian fat-tailed scorpion (A. australis), for instance, has an intravenous LD50 of 260 µg/kg (a fatal dose of 18.2 mg for a 70-kg adult), and is responsible for 80% of stings and 90% of deaths from scorpion stings in North Africa. It has a body length of 10 cm (3.9 in), weighs around 15 g (0.5 oz) and has a life span of four years; it was discovered in 1758. In addition, an IV LD50 of 230 µg/kg (a fatal dose of 16.1 mg for a 70-kg adult) has been recorded for a close relative, A. mauretanicus.

The term LD50 represents the dose of venom that proves lethal to 50% of a test population.