The great majority of scorpions are not capable of causing serious harm to humans. Apart from rare anaphylactic reactions in presensitised patients, transient local effects (in particular pain) are generally the only symptoms following a sting. The reasons for this are that the venoms are only weakly toxic or that the amounts of venom injected are too small, or that the species in question rarely comes into contact with humans or is non-aggressive in its behaviour.

Beside the medically most significant species, which are described separately, there are mentions of other species that have led to cases of significant envenoming or are categorised as potentially dangerous. These species are briefly described below according to their geographical context.

South America

Bothriuridae: a series of 28 accidents caused by Bothriurus sp. (all captured and indentified) reported from the state of São Paulo, Brazil (Torres 1993). In 9 cases the sting had no effect, and in the remaining cases the main consequences of envenoming were pain, and to a lesser extent erythema and oedema. 6 patients suffered systemic symptoms, in the form of arterial hypotension (5) and vomiting (1).

Europe

Buthidae: Mesobuthus gibbosus gibbosus, found in Greece and bordering countries to the north; considered potentially dangerous (Lebez et al. 1980).

North Africa

Buthidae: Buthacus arenicola from Tunisia is considered dangerous, but there are no descriptions of envenoming in humans (Balozet 1964, Goyffon and Chippaux 1984).

  
Middle East

Scorpionidae: Rosin (1969) suggested that Nebo hierochonticus (formerly included in the family Diplocentridae, which is no longer extant) is a relatively harmless species. However, a more recent clinical study of scorpion stings from Saudi Arabia described 2 cases of severe envenoming due to this species (Annobil 1993b). One of these patients died.

Hemiscorpiidae: severe envenoming due to Hemiscorpius lepturus has been reported in western Iran (Pringle 1960, Peters 1992). In severe cases locally extensive necroses and systemic neurological and cardiovascular effects as well as haemolysis were said to occur.

Buthidae: in Iran a 12-year-old child showed signs of systemic envenoming after an Odontobuthus doriae sting (Razi and Malekanrad 2008). Until now this species was considered harmless and it is commonly offered for sale.

Southern Africa

Buthidae: according to Newlands and Martindale (1980) Buthotus trilineatus stings are "potentially fatal". This species is widespread in the Transvaal, Zimbabwe, Mozambique, East Africa and Somalia. The authors also mention the genera Uroplectes and Lychas in association with local symptoms and mild systemic effects.

India

Scorpionidae: one case of systemic envenoming in association with Heterometrus bengalensis (= Palamneus bengalensis) has been described (Shah et al. 1989). The largest members of this genus reach a length of up to 17 cm. Scorpionidae venoms are less toxic than those of most Buthidae, but the larger species have comparatively large amounts of venom (Goyffon and Kovoor 1978).

East Asia

Buthidae: Mesobuthus martensi, which is found throughout China, is classed as potentially dangerous (Balozet 1971).

Literature (biological)

Fet et al. 2000, Keegan 1980

The Scorpion Files

The Scorpion Fauna