Definition of Hercules` beetle

The Hercules beetle (Dynastes hercules) is the most famous of the rhinoceros beetles. Native to the rain forests of Central and South America, their title is well deserved, with some (exceptionally rare) males reaching 6.75 inches (170 mm) in length. It is the largest of the 6 species in the Dynastes genus, and one of the largest beetles known, being exceeded in length by only two other beetles in the family Cerambycidae, Macrodontia cervicornis (specimens of 170-175 mm are known) and Titanus giganteus (several 180+ mm specimens are known to exist). However, if the horns are excluded, this species drops considerably farther down in the size rankings. One reason for this is that the development of the horns is  allometric, as well as sexually dimorphic, and thus not strictly correlated to actual body size; it is possible for a female to be much longer, measured from eyes to abdomen, than a male, yet be considered "smaller" simply due to the absence of horns.