29. Amblyomma crassum Robinson, 1926 .

Neotropical: 1) Colombia, 2) Panama. 3) Peru, 4) Venezuela (Robinson 1926, Méndez Arocha & Ortiz 1957, Fairchild et al. 1966, Need et al. 1991, Guglielmone et al. 2021).

The only known stage of Amblyomma crassum is the female because the male described as belonging to this species in Méndez Arocha & Ortiz (1957) is treated as the male of Amblyomma sabanerae by Fairchild et al. (1966), who also addressed the difficulties involved in morphologically separating Amblyomma crassum from Amblyomma humerale and Amblyomma sabanerae . Robinson (1926) described the female of Amblyomma crassum, which was redescribed in Méndez Arocha & Ortiz (1957) and Voltzit (2007), but there are discrepancies in the morphological accounts among these authors (Guglielmone et al. 2021). Therefore, any information concerning Amblyomma crassum should be treated as provisional.

Bermúdez et al. (2018) did not recognize the presence of Amblyomma crassum in Panama, while Ortíz-Giraldo et al. (2021) excluded this tick from the ixodid fauna of Colombia. Robinson (1926) described this species from a female collected at an uncertain locality (“Darien County, Colombia ”) that, in the opinion of Fairchild et al. (1966), may lie within Panama’s territory. Panama and Colombia are provisionally included within the range Amblyomma crassum .

The Brazilian records of Amblyomma crassum in Sauter et al. (1999) and Amorim et al. (2013) lack taxonomic support and are not treated as bona fide Amblyomma crassum in Guglielmone et al. (2021). Mollericona et al. (2021) reported the presence of Amblyomma crassum in Bolivia, but this record is in need of confirmation.