ABSTRACT
B. burgdorferi sensu stricto (s.s.) was Šrst isolated in 1982 by W. Burgdorfer1 from the tick Ixodes dammini. Subsequently, I. dammini was shown to be conspeciŠc to I. scapularis so the latter name is now considered the correct name.2 Today, 17 B. burgdorferi s.l. species are well recognized around the world. Eleven of them were identiŠed in and strictly associated with Eurasia (B. afzelii, B. bavariensis, B. garinii, B. japonica, B. lusitaniae, B. sinica, B. spielmanii, B. tanukii, B. turdi, B. valaisiana and B. yangtze), while another four (B. americana, B. andersonii, B. californiensis and B. carolinensis) were identiŠed only in the USA. B. burgdorferi s.s. and B. bissettii share the distinction of being present in both the Old and the New World. In addition to the well-established populations of the above-named species another undescribed North American species was delineated from a group of atypical American strains and was proposed as genomospecies 2 (Table 96.1). Descriptions
of new species and variants continue to be recognized, so the current number of described species is probably not Šnal.
