20. Amblyomma tenellum Koch, 1844 .

ND: ND, ND (Hoffmann 1962; Sundman 1965; Delabra et al. 1996; Guzmán-Cornejo et al. 2011). Aldama: ND, B. taurus (CFPP 2014; 2016; 2018). González: (1F, CNAC00502), Cerro El Bernal, ND (Guzmán-Cornejo et al. 2011; Chaires-Grijalva & Acuña-Soto 2024) 1. Güémez: ND, B. taurus (CFPP 2016) . Llera: ND, B. taurus (CFPP 2019) . Soto la Marina: ND, B. taurus (CFPP 2015; 2016); (19F, 10M, LAFC000480) Ejido El Sabinito, leaf litter (Present study). Tampico: (1F, 2M, 51N, CNAC00512) Rancho La Bolsa, B. taurus (Guzmán-Cornejo et al. 2011); (2F, CNA00502), Rancho La Bolsa, ND (Guzmán-Cornejo et al. 2011; Chaires-Grijalva & Acuña-Soto 2024) 1. Victoria: Ciudad Victoria, C. lupus familiaris (Carvajal et al. 2012); (1F, 1M) Ciudad Victoria, C. lupus familiaris (Rodríguez-García et al. 2023); (98F, 19M, LAFC000482) Ejido Santa Ana, C. lupus familiaris; (3F, 2M, LAFC000481) Ejido La Libertad (Parque Ecológico Los Troncones), C. lupus familiaris (Present study).

Distribution: Sierra Madre Oriental Province, Tamaulipas Province, and Veracruzan Province.

Note: The species Am. tenellum was recorded as Am. imitator until it was reestablished by Nava et al. (2014b).