120. Amblyomma tenellum Koch, 1844a .

Nearctic: 1) Mexico (north), 2) USA; Neotropical: 1) Costa Rica, 2) Guatemala, 3) Honduras, 4) Mexico (south); 5) Nicaragua (Becklund 1959, Instituto Intermaericano para la Cooperación en Agricultura 1988, Alvarez et al. 2005, Guzmán-Cornejo et al. 2011, Nava et al. 2014 c, Corn et al. 2016, Ḑttmann et al. 2016, Guglielmone et al. 2021).

Amblyomma tenellum was long treated as a synonym of Amblyomma cajennense . This changed when Nava et al. (2014c) compared the types of Amblyomma tenellum and Amblyomma imitator, described by Kohls (1958), and found them to be identical. Therefore, Amblyomma tenellum was reinstated as a valid species and Amblyomma imitator became its synonym. Most records of Amblyomma tenellum have been published under the name Amblyomma imitator .

Serra-Freire & Mello (2006) stated that Amblyomma tenellum (under the name Amblyomma imitator) has been found in Brazil. However, this statement was considered unconfirmed by Dantas-Torres et al. (2009), and Brazil is excluded from the geographic distribution of Amblyomma tenellum .