Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXIII. \u3cem\u3eButhus\u3c/em\u3e (Buthidae), with description of two new species

New data are presented on the distribution of the genus Buthus Leach, 1815 in the Horn of Africa, mainly in Somaliland, acquired during expeditions in 2011–2019. Buthus berberensis Pocock, 1900, for which the exact locality was not known, was collected again. B. zeylensis Pocock, 1900 is restored from synonymy and elevated to species rank, based on a study of 75 recently collected specimens. Two new species, B. pococki sp. n. and B. somalilandus sp. n., are described, fully complemented with color photographs of live and preserved specimens, as well as their habitats. In addition to the analyses of external morphology we also described karyotypes of selected species. B. awashensis, B. pococki sp. n. and B. zeylensis have karyotypes with 2n=22. The karyotype of B. berberensis possesses 21 chromosomes, probably as a consequence of heterozygous fusion that is evident as a trivalent during postpachytene in this species. A key and distribution map of Buthus in the Horn of Africa (five species) are included