1a.)  Palps relatively long; article ii + iii as long as or longer than width of the basis


1b.)  Palps relatively short; article ii + iii (may be fused together) shorter than width of basis


 2a.)  Coxae I internal spur long, external small, ventral basis lacks distinct auriculae


2b.)  Coxae I internal and external spurs small but distinct, auriculae prominent and sharply pointed

Ixodes ventalloi

3a.)  Genital aperture arched

Ixodes ricinus

3b.)  Genital aperture wavy or straight

for key 3b

Ixodes persulcatus

4.)  Palp not club-shaped, article iii no wider than article ii (division visible between articles)


5a.)  Coxae I with internal spur

Ixodes hexagonus

5b.)  Coxae I without internal spur


6.)  Tarsus I noticeably thick relative to length

Ixodes canisuga