Observations on the subgenus Argas (Ixodoidea: argasidae: Argas). 17. Argas (A.) polonicus sp. n. parasitizing domestic pigeons in Krakow, Poland.

Argas (A.) polonicus sp. n. is described from males, females, nymphs, and larvae from the steeple tower of St. Mary's Church, Karkow, Poland, where it feeds on domestic rock pigeons, Columba livia Gmelin. This species is related to the widely distributed Eurasian A. (A.) vulgaris Filippova and to certain other species of the eastern area of the Palearctic Faunal Region; it differs distinctly from A. (A.) reflexus (Fabricius) of western Europe. Comparative study under the light microscope. and especially under the scanning electron microscope, reveals numerous structural differences in adult and immature stages of these species, chiefly in the Haller's organ roof of each stage, adult body shape and integumental formations, dental formulae, and setal lengths and numbers on the larval dorsum.