A global review of medically important scorpions and scorpionism

Micaiah Ward and co-workers at Florida State University recently published an extensive review of medically important scorpions, epidemiology and scorpionism. The number of medical important species is raised to 104 (Buthidae: 101, Hemiscorpiidae: 2, Scorpionidae: 1). Of these, 36 species are considered dangerous (causing class II and III symptoms).

It is important to understand that a list like this can not be perfect. The species identification in many sting cases can be missing or wrong. Taxonomy is changing, and a species may turn out to be a species complex with potentially different venom potency (e.g. The Buthus occitanus complex). We should be careful not to label all species not on this list as harmless. A dangerous species may never have stung a human or the sting case was never reported. Also, many stings are dry or a reduced amount of venom is used, causing minor/mild symptoms and by this camouflaging a dangerous species. The article discuss some of these conserns.

 The article also has information about the distribution of medically important species, venom composition and the use of scorpion venom in biomedical research.

Abstract:
Scorpions are an ancient and diverse venomous lineage, with over 2200 currently recognized species. Only a small fraction of scorpion species are considered harmful to humans, but the often life-threatening symptoms caused by a single sting are significant enough to recognize scorpionism as a global health problem. The continued discovery and classification of new species has led to a steady increase in the number of both harmful and harmless scorpion species. The purpose of this review is to update the global record of medically significant scorpion species, assigning each to a recognized sting class based on reported symptoms, and provide the major toxin classes identified in their venoms. We also aim to shed light on the harmless species that, although not a threat to human health, should still be considered medically relevant for their potential in therapeutic development. Included in our review is discussion of the many contributing factors that may cause error in epidemiological estimations and in the determination of medically significant scorpion species, and we provide suggestions for future scorpion research that will aid in overcoming these errors.

Reference:
Ward MJ, Ellsworth SA, Nystrom GS. A global accounting of medically significant scorpions: Epidemiology, major toxins, and comparative resources in harmless counterparts. Toxicon. 2018;151:137-55. [Subscription required for full text]

Thanks to Matt Simon for informing me about this article!