Eastern Hercules beetle, Dynastes tityus (Linnaeus) (Coleoptera: Scarabeidae). Photo by Drees.
Common Name: Eastern Hercules beetle;Elephant beetle or ox beetle
Scientific Name: Dynastes tityus (Linneaus) (top); Strategus aloeus (Linnaeus) (bottom)
Order: Coleoptera
Description: Beetles are about 1-½ to 2-½ inches long and colored yellowish or greenish-gray with brown to black spots, rarely are they reddish- brown. Males have three projections on the shield behind the head (pronotum) with the central one the longest and nearly meeting an additional projection on the head. Females have only small raised area (tubercles) in place of the horns. Larvae are large C-shaped grubs like huge June beetles.
There are many other species of scarab beetles in Texas. The name rhinoceros beetle has been used for this species as well as the close relatives. However, the name now appropriately is applied to Xyloryctes jamaicensis (Drury). This is a dark brown species about 1 inch long and with a single long upright horn on the head of the males. Females have a small tubercle instead of a horn. Larvae feed on roots of ash trees.
The ox or elephant beetles, Strategus sp., are large (up to 2 inches long), brown rhinoceros beetles (Dynastinae). Males have three horns behind the head (on the pronotum). Immature stages look like very large white grubs and can be found in compost heaps or occasionally infest potting media.
Elephant beetle or ox beetle, Strategus aloeus (Linnaeus) (Coleoptera: Scarabeidae), grubs in potting media. Photo by Drees.
Life Cycle:There is probably one generation every year or two. Larvae take most of the year to develop and spend the winter. Adult beetles are active in the summer.
Habitat and Food Source(s): Mouthparts are for chewing. Larvae live in rotten logs or high organic matter conditions. Adults do not seem to feed much but may eat leaves.
Pest Status: Although not frequently encountered, this species is notable because of its large size and appearance; medically harmless.
Management: Not generally considered a pest.
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: Borror et al. 1989; Swan & Papp 1972; Zim & Cottam 1956.