The genus \u3cem\u3eVachoniolus\u3c/em\u3e (Scorpiones: Buthidae) in Oman

Study of new material collected in Oman by ultraviolet detection revealed three species of Vachoniolus, an unusual genus of psammophilous buthid scorpion distinguished by grossly swollen male pedipalp chelae. The presence of the type species, V. globimanus Levy, Amitai et Shulov, 1973, in Oman is confirmed, and two new species are described: V. batinahensis sp. nov. from the Al Batinah coastal plain north of the Al Hajar mountains, and V. gallagheri sp. nov. from desert alluvial fans south and west of the Al Hajar mountains. The number of Vachoniolus species is thereby raised to four, including V. iranus Navidpour et al., 2008, from northwestern Iran. Of these four, V. batinahensis appears the most plesiomorphic, with 7 external patellar trichobothria, femoral trichobothrium d5 either proximal or distal to e2, and complete retention of tibial spurs. It could be a relict descendent of an ancestral Vachoniolus population that evolved in the Tigris-Euphrates river drainage at a time when the Arabian Gulf was dry. A novel tarsal structure, the ‘spine comb’, is described in juvenile Vachoniolus, Apistobuthus and Odontobuthus. Possible mechanisms of sexual selection in the evolution of the enlarged male pedipalp chelae of Vachoniolus are discussed

Two new species of \u3cem\u3eHottentotta\u3c/em\u3e Birula, 1908 (Scorpiones: Buthidae) from northern Oman

Two new endemic species of Hottentotta Birula, 1908, are described from the Al Hajar Mountains of northern Oman: H. pellucidus sp. nov., from the Shir Plateau of Jabal Bani Jabir in the eastern Al Hajar, characterized by: medium size, uniform yellow color, dense cover of long and short macrosetae on pedipalps, legs and metasoma, only two macrosetae on tergite posterior margins, and slender male pedipalp chelae with very weakly scalloped fingers; and H. saxinatans sp. nov., from Jabal Akhdar in the western Al Hajar, characterized by: medium size, uniform yellow color with faint fuscosity on metasomal carinae, nearly bare body and appendages with few short macrosetae, and slender male pedipalp chelae with unscalloped fingers. Both are lapidicolous or lithophilic scorpions, inhabiting very rocky terrain. Their disjunct distribution in high altitude refugia suggests that they are relict species, descendents of a more widespread fauna adapted to temperate climates in the Pleistocene or post-glacial times

New picobuthoid scorpions (Scorpiones: Buthidae) from Oman

Five new species of diminutive buthid scorpions are described from Oman. Two belong to Microbuthus Kraepelin, 1898, a genus with heavily sclerotized, smooth, strongly pitted posterior metasomal segments, abbreviated telson, and pedipalps with 9 femoral and 6–7 external patellar trichobothria: M. gardneri, sp. nov., from the Al Hajar Mountains, and M. kristensenorum, sp. nov., from the Dhofar Mountains and Hadhramaut of Yemen, which was long misidentified as M. pusillus Kraepelin, 1898. Two additional new species are placed in a new genus Picobuthus, gen. nov., differentiated by granular posterior metasomal segments, elongate telson, pedipalps with 7–9 femoral and 5 external patellar trichobothria: type species P. wahibaensis, sp. nov., from the Wahiba Sands, and P. dundoni, sp. nov., from sand deserts in central Oman. A second new genus, Femtobuthus, gen. nov., is monotypic with type species F. shutuae, sp. nov., from the southern coast and plateau of Jiddat Al Harasis, differentiated by enlarged, granular, dentate metasomal segments, abbreviated telson, and pedipalps with 6 femoral and 5 external patellar trichobothria. The relationship of Microbuthus and the two new genera to other buthid scorpions is discussed, and their trichobothrial homologies are addressed. These three genera are hypothesized to represent a monophyletic ‘picobuthoid’ lineage that originated in the Arabian Peninsula

Two new \u3cem\u3eHemiscorpius\u3c/em\u3e Peters, 1861 (Scorpiones: Hemiscorpiidae) from northern Oman

Two new species of Hemiscorpius, H. falcifer, sp. nov. and H. flagelliraptor, sp. nov., are described from the Al Hajar Mountains of northern Oman. Although both are lithophilic or ultralithophilic scorpions beautifully adapted for living in rock crevices, they exhibit divergent morphologies and may not be closely related. H. falcifer is distinguished by: smaller size, relatively short compact metasoma, bulbous telson, relatively distal placement of lamellar double hook of hemispermatophore, pedipalp chela with wide, sub-triangular manus and exceptionally elongated fingers with single file dentition along distal half of movable finger (in adults); H. flagelliraptor is distinguished by: extremely elongated, sexually dimorphic metasoma, slender telson, proximal placement of lamellar double hook of hemispermatophore, slender pedipalp chela with double denticle rows along the distal half of movable finger. Although orthobothriotaxic, in other respects H. flagelliraptor appears most similar to the neobothriotaxic species H. enischnochela Monod et Lourenço, 2005 and H. gaillardi (Vachon, 1974) from Iran

A new lithophilic \u3cem\u3eCompsobuthus\u3c/em\u3e Vachon, 1949 (Scorpiones: Buthidae) from northern Oman

A new species of Compsobuthus is described from the Al Hajar mountains of northern Oman. It is distinguished by a strongly dorsoventrally compressed body, reduced carination on the carapace and tergites, extreme elongation of legs and pedipalps, lack of external accessory denticles on the pedipalp fingers, chelal trichobothrium est placed closer to dt than db, heavy setation on the ventral metasoma, and 28–34 pectine teeth. It is an ultralithophilic scorpion, highly adapted to life in narrow rock fissures

A new species of \u3cem\u3eOdontobuthus\u3c/em\u3e (Scorpiones: Buthidae) from northern Oman

The Asian buthid genus Odontobuthus is newly recorded from the Arabian Peninsula where is represented by O. brevidigitus sp. nov. from the Batínah coast and foothills of the Al Hajar mountains of northern Oman. The new species is characterized by short pedipalp fingers, long pectines with narrow basal middle lamella, 2–3 enlarged denticles on ventrosubmedian carinae of metasoma II–III, stout metasoma IV with 10 anterior transverse granules, 3 lateral anal lobes, and enlarged dentition on the ventral anal arch. A model is proposed for the speciation of Odontobuthus by westward dispersal of an ancestral population on the Indus floodplain, followed by vicariant tectonic events in the Miocene and Pliocene that led to divergence of four species in temporal sequence: O. odonturus, O. doriae, O. bidentatus and O. brevidigitus sp. nov

The genera \u3cem\u3eButheolus\u3c/em\u3e Simon, 1882 and \u3cem\u3eXenobuthus\u3c/em\u3e gen. nov. (Scorpiones: Buthidae) in Oman

The genus Butheolus Simon, 1882 is revised based on new material from Dhofar Province in Oman. B. gallagheri Vachon, 1980 is redescribed, and a related new species, B. harrisoni sp. n., is also described. The species B. anthracinus (Pocock, 1895) is redescribed and moved to a new genus Xenobuthus gen. n., that is differentiated from Butheolus by size, pedipalp finger dentition, setation, granulation and hemispermatophore structure, and a related new species, X. xanthus sp. n., is also described. Revised diagnoses are provided for the genus Butheolus, and for the species B. thalassinus Simon, 1882, and B. villosus Hendrixson, 2006, a key is given for the species examined in this study, and the status of other related species discussed

Scorpions of the Horn of Africa (Arachnida, Scorpiones). Part XVIII. \u3cem\u3eGint banfasae\u3c/em\u3e sp. n. from Somaliland (Buthidae)

Gint banfasae sp. n. from Somaliland is described and compared with other species of the genus. Additional information is provided on the taxonomy and distribution of the genus Gint, fully complemented with color photos of specimens of both sexes of the new species, as well as of their habitat. Included is a key for Gint

Review of \u3cem\u3eOrthochiroides\u3c/em\u3e Kovařík, 1998 with description of a new species (Scorpiones: Buthidae)

The genus Orthochiroides Kovařík, 1998 is reanalyzed. Revised diagnoses and new illustrations for the genus and all four of its species are presented. A new species, O. somalilandus sp. n. from Somaliland is described and illustrated. Phylogenetic relationships of the genus with several other similar genera of small buthids are inferred from a parsimony analysis of 43 discrete morphological characters. The recent synonymy of Orthochiroides with Orthochirus is refuted and the genus is revalidated

Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXIV. \u3cem\u3eLeiurus\u3c/em\u3e (Buthidae), with description of \u3cem\u3eLeiurus gubanensis\u3c/em\u3e sp. n.

New data are presented on the distribution of the genus Leiurus Ehrenberg, 1828 in the Horn of Africa, Somaliland, acquired during expeditions in 2011–2019. Leiurus gubanensis sp. n. is described from the Guban area, an extremely warm and dry place. The description is fully complemented with color photographs of live and preserved specimens, as well as of their habitats. This increases the known diversity of the genus to 14 species