English: This image illustrates the distribution of the Southern Cantil, (Agkistrodon howardgloydi). The black dot represents the type locality. It is based on text and maps published in the following.

Campbell, J. A., and W. W. Lamar 2004. The Venomous Reptiles of the Western Hemisphere (Vol. I & II). Comstock Publishing Associates, Cornell University Press, Ithaca, New York, USA. ISBN 0-8014-4141-2

Gloyd, H. K., and R. Conant. 1990. Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles, Contributions in Herpetology, Number 6, Ithaca, New York, USA. ISBN 0-916984-20-6

McCranie, J. R. 2011. The Snakes of Honduras: Systematics, Distribution, and Conservation.. Contributions to Herpetology, Vol. 26. Society for the Study of Amphibians and Reptiles. x, 714 pp. ISBN 978-0-916984-81-6

Porras, L.W., L. D. Wilson, G. W. Schuett, R. S. Reiserer. 2013. A taxonomic reevaluation and conservation assessment of the common cantil, Agkistrodon bilineatus (Squamata: Viperidae): a race against time. Amphibian & Reptile Conservation 7(1): 48–73.

Savage, J. M. 2002. The Amphibians and Reptiles of Costa Rica, A Herpetofauna between Two Continents, between Two Seas. University of Chicago Press, Chicago, Illinois. xx, 934 pp. ISBN 0-226-73537-0

iNaturalist, Explore, Observations: Agkistrodon howardgloydi (accessed 30 July 2021)

https://www.inaturalist.org/observations?place_id=any&taxon_id=497678