248 2005. The Journal of Arachnology 34:248–253 SHORT COMMUNICATION AN EXTREMELY LOW GENETIC DIVERGENCE ACROSS THE RANGE OF EUSCORPIUS ITALICUS (SCORPIONES, EUSCORPIIDAE) Victor Fet: Department of Biological Sciences, Marshall University, Huntington, West Virginia 25755-2510, USA Benjamin Gantenbein: Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK Ays ¸egu ¨ l Karatas ¸ and Ahmet Karatas ¸: Department of Zoology, Nigde University, Nigde, Turkey ABSTRACT. Little or no genetic divergence is detected using mitochondrial 16S rDNA sequence com- parisons across the entire geographic range of the scorpion Euscorpius italicus (Herbst 1800) from Swit- zerland, Italy, Slovenia, Greece and Turkey. This is consistent with known absence of patterns of allozymes and morphological variation. Euscorpius italicus is found almost exclusively in human habitations. Its sister species, E. naupliensis, exhibits much higher genetic diversity within southern Greece. We suggest that the natural populations of the thermophilic E. italicus underwent a bottleneck during the glaciations, and that its modern range could be a result of dispersal with humans. Keywords: Scorpions, genetic distance, DNA, 16S rRNA, biogeography A large, conspicuous scorpion Euscorpius itali- cus (Herbst 1800) has been known to arachnologists for 200 years and to humankind for millennia. It is commonly found in many localities in Italy and Greece, being an especially common species in hu- man habitations (Crucitti 1993; Braunwalder 2001). This species is found from the French Riviera to the northern and eastern shores of the Black Sea. Euscorpius italicus prefers a xeric microclimate (Birula 1917a, 1917b; Braunwalder 2001; Fet et al. 2001). In Italy, this species is locally very abundant and usually synanthropic. To the north of Italy it is limited by the southern Alpine valleys in Italy and Switzerland (Crucitti 1993; Braunwalder 2001); in Turkey and the Caucasus it also does not venture into high mountains (Birula 1917a, 1917b). The species’ elevational preference seems to range from 0–500 m, while reported well-isolated ‘‘island’’ populations above 500 m could be attributed to re- cent human-mediated range expansion (Braunwald- er & Tschudin 1997). Several subspecies were de- scribed in this species (Birula 1917a; Birula 1917b; Caporiacco 1950) but are currently not recognized (Kinzelbach 1975; Vachon 1981; Bonacina 1982; Fet & Sissom 2000)(Fig. 1). A detailed redescrip- tion and taxonomic history of E. italicus was re- cently published by Gantenbein et al. (2002), who also demonstrated the separate species status (well defined by both morphological and molecular cri- teria) for E. naupliensis (C. L. Koch 1837) from southern Greece, for many years considered a syn- onym of E. italicus. In order to assess the species structure of E. it- alicus, we used comparative analyses of the mito- chondrial 16S ribosomal RNA gene, a molecular marker that has been recently applied to resolve the species-level phylogeny of several species of Eus- corpius (Gantenbein et al. 1999, 2000, 2001, 2002; Fet et al. 2002, 2003); for the detailed DNA anal- ysis procedures and phylogenetic tree-building al- gorithms, see Gantenbein et al. (1999, 2000). Seven mtDNA sequences (ca. 400 base pairs each) were aligned using ClustalX 1.81 (Thompson et al. 1997). Two new DNA sequences, obtained for the present study, were deposited in GenBank (http:// www.ncbi.nlm.nih.gov) under accession numbers: EiTU1 (AY371536) Samugu ¨ney Village, Bulancak, Giresun, Turkey, 40°56'N, 38°15'E, 17 February 2003 (coll. A. Karatas ¸), and EiSM1 (AY371535) Silvi Marina, Abruzzo, Italy, 42°34'N, 14°05'E, 20 June 2000 (coll. F. Kovar ˇı ´k). Voucher specimens are deposited in the Unites States National Museum (USNM), Smithsonian Institution, Washington, DC, USA. Four additional DNA sequences of E. italicus