Acarus ricinus Linnaeus, 1758: 615.
Records in Baltic States: Estonia (Pototski et al. 1993; Vikentjeva et al. 2021), Latvia (Polikarpova 1957; Lapina 1959; 1960; 1961; Grinbergs 1960; 1961a; 1961b; 1961d; 1964; Salmane 2012), Lithuania (Likevičienė 1957; Podėnaitė 1960; 1979; Jezerskienė 1974; Arnastauskienė et al. 1989; Paulauskas et al. 2009; 2010; 2011; Radzijevskaja et al. 2018; current study).
Hosts: N. fodiens (LT), S. araneus (EE, LV, LT), S. minutus (LV, LT), S. betulina (LT), A. agrarius (EE, LV, LT), A. flavicollis (EE, LV, LT), A. sylvaticus (LT), M. minutus (LT), M. musculus (LV, LT), A. oeconomus (LT), A. amphibius (LV, LT), C. glareolus (EE, LV, LT), M. agrestis (LV, LT), M. arvalis (LV, LT).
Host specificity: generalist parasite ( S i = 0.25).
European distribution: Albania, Austria, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Finland France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Kosovo, Luxemburg, Malta, Moldova, Montenegro, the Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Spain; Sweden, Switzerland, Ukraine, the United Kingdom (Černy 1972; Haitlinger 1979; 2011; 2015; Martyn 1988; Petrović & Milutinović 1993; Ruzić-Sablijić et al. 1993; Jaenson et al. 1994; Chikilevskaya et al. 1998; Walter 2000; Santos-Silva et al. 2006; García-Sanmartín et al. 2008; Xhaxhiu et al. 2009; Coipan et al. 2011; Capelli et al. 2012; Krčmar 2012; Pavlović et al. 2014; 2020; Ponomareva et al. 2015; Papa et al. 2016; Maaz et al. 2018; Hornok et al. 2020; 2022a; 2022b; Akimov & Nebogatkin 2022; Blazhev et al. 2022; Lebert et al. 2022; Omeragić et al. 2022; Pascucci et al. 2022; Rubel & Brugger 2022).