253. Ixodes unicavatus Neumann, 1908a .

Palearctic: 1) France, 2) Great Britain, 3) Ireland, 4) Netherlands, 5) Sweden, 6) Ukraine (Filippova 1977, Guiguen & Beaucournu 1984, Martyn 1988, Jaenson et al. 1994, Estrada-Peña et al. 2017).

Some records of Ixodes unicavatus have been published under the name Ixodes tauricus, a tick described by Vshivkov & Filippova (1957) but found to be a synonym of Ixodes unicavatus by Filippova (1977).

Gothe et al. (1977) found a female Ixodes on a dog in Germany with one porose area on the basis capituli. These authors treated this specimen as an aberrant individual of Ixodes canisuga but left open the possibility that the tick may represent Ixodes unicavatus, a species characterized as having one porose area on the basis capituli. Petney et al. (2012) regarded this specimen as Ixodes unicavatus, a statement considered unconfirmed here.