Evolution of the tissue factor pathway inhibitor-like Kunitz domain-containing protein family in Rhipicephalus microplus

► A family of 42 TFPI-like Kunitz proteins was found in Rhipicephalus microplus. ► Ancient and recent gene and domain duplications caused expansion of the family. ► Estimated tick lineage divergence times correspond with those of previous studies. ► Evidence for a whole genome duplication event 150 million years ago was found.