Delta Flower Scarab Beetle is Master of Disguise
Les Harrison is the Wakulla County Extension Director
Halloween masks are big business for retailers attracting customers in October. After all, what child could refuse being a super hero, princess, or a hideous freak of nature while getting a sack full of candy?
In reality, the tactic of appearing to be something intimidating is fairly common. It is especially useful in the untamed world where the strong regularly eat the weak.
Wakulla County has one native insect which is currently employing a mask as a ruse to alarm anyone or anything which comes too close. The Delta Flower Scarab Beetle (Trigonopeltastes delta) uses its disguise for the purpose of staying off the menu.
This common name refers to the triangular pattern on the center of its back. The shape resembles the Greek letter delta. This beetle is sometimes known as the “D beetle.”
The species is very active during daylight and easy to view in late summer and autumn. It is most commonly seen in and around flowers in bloom.
Delta flower scarab beetles are members of the subfamily commonly called fruit or flower chafers. The common June Bug or June Beetle is a member of this group.
There are around 4,000 species worldwide and they are on every continent except Antarctica. These beetles are usually seen only in their adult life stage.
This beetle begins life as a white grub which lives underground and is capable of serious damage to plants by feeding on their roots, especially turf grasses. Turf damage becomes apparent with brown patches appearing as the grubs continue to feed and mature during the late summer and fall.
When the grub population is high and damage severe, the grass may be rolled back like a rug. The turf roots are completely gone, destroyed by the large, segmented white grubs.
These beetle grubs are a food source for a variety of birds and animals seeking easy late-season nourishment. Unfortunately the predators such as crows, skunks and raccoons may further damage the lawn by digging for this favored food.
As adults they spend their days on flower blossoms, especially goldenrods in Wakulla County. Their diet is mainly pollen and it is where these beetles mate, but it is a dangerous environment for these brightly colored insects.
Many birds and other animals instinctively know there are many choice meals on the attractive blooms. However, this beetle has a unique defense in the form of a threatening mask.
When threatened, the delta flower scarab beetle turns away from the hazard. It then raises its hind legs forward, slants its body upwards emphasizing the upper shell with the delta marking.
The harmless beetle now has the appearance of a large hornet’s head. Even the most aggressive predators stop to evaluate their gain versus their potential pain giving the beetle time to fly to safety.
Success for this native insect may not be a sack full of candy treats sought by others wearing masks, but at least it is not a snack for a hungry bird.
To learn more about the delta flower scarab beetle in Wakulla County, visit the UF/IFAS Wakulla County Extension Office at call (850) 926-3931.