Genus: Huehuecanuhtolus RAMIREZ-VELASCO, BENAMMI, PREITO-MARQUEZ, ORTEGA, & HERNANDEZ-RIVERA, 2012
Etymology: The generic name is composed of the nahuatl (group of dialects related to the Aztecan languages) words huehutel for "ancient" and canauhtli for "duck," and Greek, tholos, "dome." In reference to its hadrosauroian affinities.

Species: tiquichensis RAMIREZ-VELASCO, BENAMMI, PREITO-MARQUEZ, ORTEGA, & HERNANDEZ-RIVERA, 2012
Etymology: In reference to the town of Tiquicheon, Michoacan State, Mexico, honoring the generosity and hospitality of its people during the fieldwork season.

Holotype: IGM 6253

Locality: Sixth fossiliferous spot, Barranca Los Bonetes, Tuzantla, Michoacan State, Mexico.

Horizon: Unnamed formation.

Biostratigraphy:

Age: Santonian Stage, Lower Senonian subepoch, Middle Gulf Epoch, Late Cretaceous.

Material: A partial left maxilla, dentary fragment, 4 cervical vertebrae (including the axis), 9 dorsal vertebrae, 4 dorsal neural spines, 1 dorsal diapophysis, 5 right dorsal ribs, 7 left dorsal ribs, 7 sacral neural spines, 7 sacral diapophysis, 1 caudal diapophysis, 3 caudal vertebrae, 2 caudal neural spines, 8 fragmentary ossified tendons, left and right partial ilium, and left and right partial pubis from the 6th spot.

Note: 2 dorsal ribs and a dorsal vertebra with pathologies; possible premortem or perimortem anterior rib fracture, associated with a singular sclerosis and costovertebral ankyloses which probably originated by spinal and rib osteomyelitis (RAMIREZ-VELASCO, MORALES-SALINAS, HERNANDEZ-RIVERA, & TANKJE, 2016.

Paratype: IGM 6254

Locality: Third fossiliferous spot, Barranca Los Bonetes, Tuzantla, Michoacan State, Mexico.

Horizon: Unnamed formation.

Biostratigraphy:

Age: Santonian Stage, Lower Senonian subepoch, Middle Gulf Epoch, Late Cretaceous.

Material: Fragment of left dentary, 2 teeth, and 1 cervical prezygapophysis of a smaller individual.