Hemiscorpiidae (Scorpiones) from Iran, with descriptions of two new species and notes on biogeography and phylogenetic relationships

The family Hemiscorpiidae is closely related to the Liochelidae. Within the Hemiscorpiidae, the Oriental species are particularly interesting. Most of them exhibit highly derived characters in comparison to their African relatives. Males possess a strongly elongated metasoma and a similarly elongated telson bearing a pair of tuberculiform processes at the base of the aculeus. Furthermore, Hemiscorpius lepturus Peters, 1861, which occurs in Iraq and Iran, is known to have an extremely virulent venom with cytotoxic and haemolytic components. It is responsible for severe dermonecrotic scorpionism in southern Iran. This is the only non-buthid scorpion that is potentially lethal. In this paper an overview of the species of Hemiscorpius in Iran is presented with revised diagnoses and descriptions. Two new species from western Iran, H. enischnochela sp. n. and H. acanthocercus sp. n., are described. The genus Habibiella Vachon, 1974 is synonymised with Hemiscorpius Peters, 1861. A thorough analysis of hemispermatophores shows close phylogenetic relationships with several genera of the family Liochelidae. A hypothesis on the geological events that probably triggered the present distribution of Hemiscorpius is finally proposed.