Hyaenodon horridus (Hyaenodon Leidy, 1869)
Time period: late Eocene and early Oligocene (North America)
Size: Up to 1,8 meters long. 80 cm tall at the shoulder. Weight estimated at up to 50 kg.
Hyaenodon horridus ("hyaena-toothed") is an extinct genus of Hyaenodonts, a group of carnivorous creodonts of the family Hyaenodontidae endemic to all continents except South America, Australia and Antarctica, living from 42-15.9 mya, existing for approximately . The average weight of adult or sub-adult Hyaenodon horridus, the largest North American species, is estimated to be about 40 kg and may not have exceeded 60 kg.