Ixodes barkeri n. sp. (Acari: Ixodidae) from the short-beaked echidna, Tachyglossus aculeatus , with a revised key to the male Ixodes of Australia, and list of the subgenera and species of Ixodes known to occur in Australia

A new species of Ixodes is described from two male specimens that have a distinctive ventrolateral horn-like projection on palpal article 1. This structure is not found in any other Australian species, but is similar to that of I. zaglossi Kohls, 1960 from the long-beaked echidna of Papua New Guinea. I present a revised key to accommodate the five males of Australian Ixodes described or re-described since 1970. I also briefly review the 26 Australian species of Ixodes.