1. Acarine group, for example, ixodid ticks have 1 nymphal instar and some argasid ticks have up to 8 nymphal instars

2. Significantly elevated antibody titers against ixodid tick spirochetes were observed in 45% of 44 cases with erythema migrans disease, in 72% of 29 cases of lymphocytic meningoradiculitis, in all of nine patients with acrodermatitis chronica atrophicans and in all of four investigated patients with lymphocytoma (lymphadenosis benigna cutis).