Owen (2011) published an uncertain record as “ Ixodes? trichosuri ” from Papua New Guinea, and this country is therefore not included within the geographic distribution of Ixodes trichosuri.
McCann et al. (2019) presented molecular evidence suggesting that more than one species may exist under the name Ixodes trichosuri.
248. Ixodes tropicalis Kohls, 1956a. Neotropical:1) Colombia, 2) Peru (Trapido & Sanmartín 1971, Guglielmone et al. 2021, Quintero et al. 2021a).
249. Ixodes turdus Nakatsudi, 1942a. Oriental: 1) India, 2) Taiwan; Palearctic: 1) Japan (except the Ryukyu Islands), 2) Nepal (north and central), 3) South Korea (Rao et al. 1973, Clifford et al. 1975 a, Miyamoto et al. 2000, Sames et al. 2008, Kuo et al. 2017).
Guglielmone & Robbins (2018) listed Taiwan (Oriental) within the geographic distribution of Ixodes turdus but regarded this species as found only in the Palearctic Region. These authors also excluded India from this species’ range, but its presence in India is based on Rao et al. (1973). Specimens of Ixodes turdus from Nepal and Japan are close morphologically (Clifford et al. 1975a), but also molecularly (Xu et al. 2003, Takano et al. 2014), and Nepal is therefore included within the range of Ixodes turdus, a tick described from specimens collected in Japan.
Bolotin & Kolonin (1979) found Ixodes turdus on migratory birds in the Russian Far East but believe that this tick is not established there, an opinion also shared by Tsapko (2020), and that territory is excluded from the range of Ixodes turdus.
250. Ixodes ugandanus Neumann, 1906. Afrotropical: 1) Cameroon, 2) Kenya, 3) Mozambique, 4) Nigeria, 5) South Africa, 6) Tanzania, 7) Uganda, 8) Zimbabwe (Yeoman & Walker 1967, Walker 1974, Keirans & Brewster 1981, Matthysse & Colbo 1987, Norval et al. 1987, Kolonin 2009, Horak et al. 2018).
251. Ixodes uilenbergi Apanaskevich & Goodman, 2020b. Afrotropical: 1) Madagascar (Apanaskevich & Goodman 2020b).
252. Ixodes uncus Apanaskevich & Goodman, 2020b. Afrotropical: 1) Madagascar (Apanaskevich & Goodman 2020b).
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.