Mesobuthus Vachon, 1950

Lourenço, Wilson R., Qi, Jian-Xin & Zhu, Ming-Sheng, 2005, Description of two new species of scorpions from China (Tibet) belonging to the genera Mesobuthus Vachon (Buthidae) and Heterometrus Ehrenberg (Scorpionidae), Zootaxa 985, pp. 1-16 : 2-3

Genus Mesobuthus Vachon, 1950

Historical account

In the early 1940s, Vachon (1952) began a series of studies on the scorpions of North of Africa. One of his main preoccupations was with the definition of the various groups of species within the genus Buthus Leach. This led to the subdivision of what was at that time the genus Buthus into about 10 separate genera. Two of the genera proposed by Vachon were Buthotus Vachon, 1949 and Mesobuthus Vachon, 1950 . The first, Buthotus , comprised the majority of species that had been included in the old subgenus Hottentotta Birula, 1908 . Kraepelin (1891) was in fact the first author to distinguish a Hottentotta group (species­group) within the genus Buthus . Most of the species included were allied to Buthus Hottentotta (Fabricius) . Birula (1908) created the subgenus Hottentotta , without, however, a clear diagnosis. Vachon (1949) disregarded Hottentotta Birula and established a new name, Buthotus . Hottentotta is, however, a valid senior synonym for Buthotus , and was re­established by Francke (1985). Other valid subgenera in addition to the nominotypical Hottentotta are Balfourianus which was described by Vachon (1979) to include the species Hottentotta socotrensis (Pocock) which is endemic to the Island of Socotra, and Deccanobuthus described by Loureno (2000) for the species Hottentotta (Deccanobuthus) geffardi from India.

In their exhaustive study of the genus Buthotus (= Hottentotta ), Vachon and Stockmann (1968) recognized and defined several lineages and sub­lineages of Hottentotta . Both authors, as well as Vachon and Kinzelbach (1987), suggested that the African, Saharo­Sindian and Indian lineages might be different. In fact, several species originally thought to belong to the Indian lineage are currently placed in the genus Mesobuthus Vachon, 1950 (see also Tikader & Bastawade 1983). In addition to its association with Hottentotta , the genus Deccanobuthus also shows affinities with the genus Mesobuthus and, because of its very marked carination, the new Mesobuthus species described here, could also be accommodated in this last genus. However, according to Fet and Lowe (2000), the relationships of Mesobuthus to other genera, and in particular to Hottentotta remain poorly defined. According to V. Fet (personal communication), the clarification of this situation will require a careful analysis of clusters of true Mesobuthus versus African and Middle­East Hottentotta , with the possible definition of new characters. The DNA tree proposed by Fet et al. (2003) shows that Mesobuthus is much closer to Compsobuthus Vachon that it is to Hottentotta , but, for this study only few Hottentotta species have been analysed. For this reason, we believe that only after a revision of all the species assigned to these different genera has been made, a definitive conclusion regarding their precise status can be reached.