Genus: Infernolestes CIFELLI, DAVIS & SAMES, 2014
Etymology: Latin, infernus, "hell"; in reference to Hell Canyon, from which the holotype was discovered, and to the conditions endured at the type locality, and Greek, lestes, "theif, robber."

Species: rougieri CIFELLI, DAVIS & SAMES, 2014
Etymology: In honor of Guillermo Rougier, for his contributions to the knowledge of Mesozoic mammals.

Holotype: OMNH 62671

Locality: OMNH V1243, near the mouth of Hell Canyon, Section 26, township 8S, Range 4E, N43°19', W103°37', about 17 ENE of Edgemont, Fall River County, South Dakota.

Horizon: Chilson Member, Lakota Formation.

Biostratigraphy:

Age: Berriasian-Valangian Stage, Lower Neocomian Subepoch, Lower Early Cretaceous Epoch, Early Cretaceous.

Material: Right lower molar, identified as m1.