Geographic distribution of the hard ticks (Acari: Ixodida: Ixodidae) of the world by countries and territories Author Guglielmone, Alberto A. 0000-0001-5430-2889 guglielmone.alberto@inta.gob.ar Author Nava, Santiago 0000-0001-7791-4239 nava.santiago@inta.gob.ar Author Robbins, Richard G. 0000-0003-2443-5271 robbinsrg@si.edu text Zootaxa 2023 2023-03-07 5251 1 1 274 http://dx.doi.org/10.11646/zootaxa.5251.1.1 journal article 235222 10.11646/zootaxa.5251.1.1 43227427-a867-4744-9e4c-2b2302524890 1175-5326 7704190 3326BF76-A2FB-4244-BA4C-D0AF81F55637 41. Ixodes canisuga Johnston, 1849 . Palearctic: 1) Austria , 2) Belgium , 3) Bosnia and Herzegovina , 4) Croatia , 5) Denmark , 6) France , 7) Germany , 8) Great Britain , 9) Hungary , 10) Ireland , 11) Italy , 12) Latvia , 13) Lithuania , 14) Netherlands , 15) Poland , 16) Portugal , 17) Romania , 18) Serbia , 19) Slovenia , 20) Spain , 21) Sweden , 22) Switzerland ( Manilla 1985 , Martyn 1988 , Fain 1990 , Jaenson et al. 1994 , Trilar 2004 , Cringoli et al. 2005 , Santos-Silva et al. 2011 , Petney et al. 2012 , Obsomer et al. 2013 , Hornok et al. 2017b , Krčmar 2019 , Karbowiak et al. 2020 , Hornok et al. 2021 , Rubel & Brugger 2022 ). Guglielmone et al. (2020) described the confusion of Ixodes canisuga with related species. Ixodes canisuga was treated as a valid species in Filippova & Uspenskaya (1973) and Teng (1973) , but later Filippova (1977) and Teng & Jiang (1991) regarded this name as a synonym of Ixodes crenulatus , and this thinking was followed by Kolonin (2009) , although both species, Ixodes canisuga and Ixodes crenulatus , are considered valid here. Nevertheless, many records of these species require confirmation, and the range of Ixodes canisuga should be regarded as provisional. This uncertainty is underscored by the fact that there are several synonyms of Ixodes canisuga , as detailed in Petney et al. (2012) and Guglielmone & Nava (2014) . The presence of Ixodes canisuga in Slovenia is based on Trilar (2004) . Ixodes canisuga was treated as a tick found in China by Zhao et al. (2020) and others. These authors cited Teng (1973) in arguing for the presence of Ixodes canisuga in China , while ignoring the synonymy of this species with Ixodes crenulatus in Teng & Jiang (1991) . Zhao et al. (2020) did not discuss that synonymy, being uncertain as to how to treat these names. Chen et al. (2010) , Zhang, G. et al. (2019), Zhang, Y.K. (2019) and Zhao et al. (2021) did not include Ixodes canisuga as occurring in China , a country that is provisionally excluded from the range of this tick. Estrada-Peña et al. (2017) listed both Ixodes canisuga and Ixodes crenulatus as found in China . It is apparent that there is a need for additional research to properly define Ixodes canisuga , Ixodes crenulatus and related species, based on analyses of specimens throughout their ranges.