[2] This name is contentious as the description was produced online before 2011, and is therefore against the Code of Zoological Nomenclature.

The head is long and narrow, resembling the shape of an arrowhead.

[2] The Patian lancehead is distributed within the upper Patía river valley Departments of Cauca and Nariño, southwestern Colombia.

[4] Bothrops ayerbei exhibits sexual dimorphism mainly in the number of scales the different sexes have.

[2] However, it exhibits sexual dimorphism in colours as well, specifically as neonates, with males displaying yellow on their tails.