The Hercules Beetle is actually a subclass of Rhinoceros beetles with two large horns protruding from its thorax and head. These distinct horns along with its enormous size make the beetle easy to identify. The last larval stage is the size of the average Twinkie; that’s big enough to fill the palm of an average adult’s hand. There are several more strange Hercules beetle facts, which is perhaps why they are garnering attention as pets in some trendy areas of the country.
Hercules grubs can reach up to four and one-half inches and adult males can reach upwards of six and three-quarter inches. The largest of the Dynastes genus, it is one of the largest beetles in existence; only two other beetles (both in their family) have been found that are longer. The length of these beetles is attributed to their horns and the length of their horns is a direct result of the quality and amount of nutrients it received during the larval and pupal stages.
How big is this horn? Pretty big. It is almost a third of the length of the beetle and ranges from two to three inches. The reason for the great size of the horns? They use them to pick up other males during the mating season and slam them down to the ground to break their heads. Thus, the longer the horns on the male beetle are the more likely that particular beetle will win the fight and in turn, win the female.
The other major feature of the male is the coloration of its thorax and elytra. These parts of the exoskeleton can be in a range from light green to dark brown with pronounced black spots. Females are almost always a dark brown. When these beetles are first removed from the soil or a tree stump the black spots may not be visible and the beetle could be misidentified. The shell will absorb moisture and become almost black. Luckily the beetle will dry quickly and the lighter color and trademark spots will appear.
The Hercules beetle is often referred to as the strongest creature on earth for its size. Although it is capable of carrying 850 times its own body weight in a laboratory experiment, Rob Knell from Queen Mary, University of London and Leigh Simmons from the University of Western Australia found that the dung beetle is stronger. The genus Onthophagus Taurus was able to move 1,141 times its own body weight making it proportionately the strongest creature in the world.
Hercules beetles are native to Central America and South America and the temperate regions of The United States. The largest varieties are found in Honduras while the smallest can be found in the eastern Appalachian valleys of Kentucky. The adult beetles are almost always found on or in close proximity to the ground. They scavenge for food but spend the majority of their adult lives searching for a mate. They live in rotted tree trunks and composting heaps of organic matter.
Diet and Predators
Hercules beetle grubs eat decaying organic materials. This includes soft woods, fallen leaves, rotting fruit and in some cases, the bark of the ash tree. As grubs, the Hercules larva spend a great deal of time under the soil, which makes them prime prey for digging mammals like skunks and raccoons as well as arthropods like centipedes, ground beetles and spiders. Even before they hatch, the eggs are preyed on by mites and Mydas fly maggots.
If a Hercules Beetle does manage to survive the maggots, mites, raccoons, skunks, centipedes and spiders, it could live to a ripe old age of 18 to 20 months. The first 11 to 16 months are spent underground as eggs, instars and pupa, while the final three or four are spent above ground as adults searching for a mate.
The beetles undergo a complete metamorphosis cycle beginning with the egg stage, which lasts about a month, three larval stages that last from six months to a year, the two or three-week pupal stage in which the larva reorganizes an develops the hard exoskeleton and other adult parts, and the final adult stage that lasts until shortly after reproduction.
Adult beetles do not emerge from the soil until the spring. The females immediately begin releasing pheromones to attract males. After mating, the females burrow into the ground to lay eggs and start the process all over again.
Many people are apprehensive about touching these beetles because of their large front horns. In actuality, the only way that a Hercules beetle could hurt a person is by scratching them with the sharp claws at the end of each leg and even then it wouldn’t be because the beetle was malevolent but rather because it is scared.
- Image by How I See Life @ FlickR under Creative Commons License 2.0, http://www.flickr.com/photos/mrsbluff/2147556964/sizes/m/in/photostream/
- “Strongest Animal.” Extreme Science | Science Technology | Earth Science. Web. 29 Aug. 2011. http://www.extremescience.com/zoom/index.php/creepy-crawlies/117-strongest-animal
- “Hercules Beetle Facts - National Zoo| FONZ.” Welcome to the National Zoo| FONZ Website - National Zoo| FONZ. Web. 29 Aug. 2011. http://nationalzoo.si.edu/Animals/Invertebrates/Facts/insects/Herculesbeetles.cfm
- Wallin, Bill. “Hercules Beetles of Kentucky - University of Kentucky Entomology.” University of Kentucky. Web. 29 Aug. 2011. http://www.uky.edu/Ag/CritterFiles/casefile/insects/beetles/hercules/hercules.htm