
common name: cicada killer, giant ground hornet
scientific name: Sphecius speciosus (Drury) (Insecta: Hymenoptera: Sphecidae)
The fertilized female begins the reproductive cycle by making burrows 0.3 to 1.2 meters in length, with numerous branches and cells. The front legs rake the soil which is pushed out behind the female with her hind legs, resulting in a large dirt mound. The burrows are left open during provisioning and may never be closed. However, the cells are carefully closed when completed. From one to four cicadas per cell are deposited depending on the size of the cicada.
The female paralyzes the host by stinging the membrane at the base of the foreleg, then carries
the cicada venter to venter by dragging or flying to the nest. One egg is placed on the last cicada
in each nest. Apparently, the mother wasp can determine the sex of the egg and places the female
egg with the more abundant provisions. Lin and Michener (1972) saw up to four females of S.
speciosus provisioning a single nest simultaneously which may indicate a step toward sociality.
Key to Species of Sphecius in Florida
1. Body predominately rust orange color with mostly black antennae and last few segments of
the abdomen black . . . . . Sphecius hogardii (Latreille)
1'. Body predominately black with first three abdominal segments with large yellow spots; legs,
mesoscutellum, and part of vertex rust orange color . . . . . Sphecius speciosus (Drury)
Sphecius hogardii (Latreille)
This is a Caribbean species known from the Florida Keys (Key West) and here newly recorded
from Lover's Key, Lee County, Florida, 16 July 1999, C. Porter and L. Stange, collectors. It
appears to be uncommon in Florida and nothing is known of its host preferences. The rust
orange coloration is distinctive. However, the black on the abdomen is variable. The Bahama
populations lack the black coloration (subspecies bahamas Krombein)
S. hogardii
Sphecius speciosus (Drury)
This wasp is widely distributed east of the Rocky Mountains and south into Mexico. Sometimes
common locally in Florida especially during the summer months where many wasps may nest
together gregariously. Human encounters with this giant wasp are only seemingly dangerous
since usually it is the stingless male which is the aggressor. The four foot burrows may have
more than 16 cells which contain one to two cicadas each of many species of Tibicen. The wasps
are parasitized by sarcophagid flies (Senotainia trilineata (Wulp); Metopia argyrocephala
(Meigen)) and possibly mutillid wasps.
S. speciosus
Management
Cicada killers are usually considered beneficial insects since they destroy plant feeding cicadas.
Also, they rarely sting except when the females are handled. However, under certain
circumstances such as when elderly persons or young children are present in the breeding areas
one may want to discourage their presence. This can be done by eliminating or reducing the
breeding area which usually consists of exposed, sandy soil. This area can be mulched or covered
with grass. Labeled insecticides can be applied to the nesting sites to kill the wasps.
Selected References
Author: Lionel A. Stange, Division of Plant Industry, Florida Department of Agriculture and Consumer Services
Originally published as DPI Entomology Circular 402.
Photographs: Division of Plant Industry,
Project Coordinator: Thomas R. Fasulo, University of Florida
Publication Number: EENY-295
Publication Date: June 2003
Copyright 2003 University of Florida
Featured Creatures
Department of Entomology and Nematology
Division of Plant Industry
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