We have two species under the Genus Dynastes in the U.S. Dynastes grantii Horn and Dynastes tityus (Linnaeus) in western states and eastern states respectively, so-called Western Hercules Beetles and Eastern Hercules Beetles. Two species are not yet known to occur in the same region, and the habitat environment is very different as well.

The two are easily distinguishable in larger males, but can you identify and describe them scientifically? Here I will discuss how to identify and differentiate them based on their morphological characters. I hope readers can understand and be capable to distinguish one another after reading this Insect Brothers Library article.

(Ratcliffe and Cave (2017))

Dynastes grantii Horn is known to occur abundantly in the state Arizona, but rarely found in New Mexico and Utah. Also, it is considered to be Species of Greatest Conservation Need (SGCN) in New Mexico. They occur in dry high altitude flat.

Dynastes tityus (Linnaeus) is known to occur from western Texas east to Florida, north to New York. Although D. tityus is known in wide range of states, they are less abundant compared to D. grantii. They occur in humid low altitude heavily forested areas.