Unicorn Beetle
Dynastes tityus - (Family: Scarabaeidae)



Male Unicorn Beetle

The unicorn beetle, or Hercules beetle, is a particularly striking insect. Some exceed 2 1/2 inches in length. The male has a conspicuous horn that may be as much as 2 inches long, but usually less, making this beetle an attractive addition to an insect collection. Unicorn beetles are rare.

The Unicorn/Hercules beetle is the largest beetle in the United States. The males have a pair of horns extending forward on the head. The females are slightly smaller and their horns are less prominent than those of the males. The main food source for the adult is plant sap. The beetle rubs the tender bark on the plant until the sap begins to run.

Eggs are laid in decaying wood matter, which is what the larva will feed on while developing. Before laying her eggs the female packs the wood material with her hind legs in the spot where she is going to lay an egg. She then inserts her ovipositor into this packed area, making a small chamber where the egg is laid. The egg incubates for three or four months

After the eggs hatch, the larva feeds on rotting wood in which they are buried. The larva grows in size and continues eating for approximately eight months. During this period it molts several times. Once the larva is fully developed it goes through complete metamorphoses and changes into an adult. Adults emerge from the wood and fly off to search for food and mates.

The very similar Eastern Hercules Beetle is a member of the same scarab beetle family. Most scarabs are stout beetles with large heads and pronotums. Many have beautiful metallic colors. The distinctive, clubbed antennae is composed of leaflike plates that can be drawn into a compact ball or fanned out to sense odors. The front tibiae are broad and adapted for digging. Although a few species lack the ability to dig.

The C-shaped larvae are yellowish or white. Both the adult and larvae are nocturnal. Many are important scavengers that recycle dung, carrion, and decaying vegetable matter. Others are agricultural pests. This large insect family consists of about 1,300 species in North America.

Female Unicorn Beetle

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