| Cicada Killer Wasp |
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| Vorlage:Taxonomy |
| Binomial name |
| Sphecius convalis |
The Cicada Killer Wasp (Sphecius convalis), sometimes also called the Sand Hornet,
although it is not a hornet (which belong to the family Vespidae), is a large, solitary wasp that occurs in North America. There are three other species of cicada killers in tNorth America: "Sphecius speciosus", "S. grandis" and "S. hogardii". Cicada killers are also found in the Carribean, Central and South American nations and in Australia [1]. For more information on cicada killers, particularly on the Eastern Cicada Killer, "S. speciosus", visit Prof. Chuck Holliday's Cicada-Killer Page [2] and Prof. Joe Coelho's Cicada Killer Thriller page [3].
Description
Adult Cicada Killer Wasps are large, 3 to 4 cm (11/8 to 15/8 inches) long, robust wasps with reddish areas on the thorax (middle part) and are marked with various combinations of reddish brown, light yellow and black stripes on the abdominal (rear) segments. The wings are russet yellow or brownish. Coloration may superficially resemble yellowjacket wasps.
Life Cycle and Habits
Solitary wasps (such as the Cicada Killer) are very different in their behavior than the social wasps (hornets, yellowjackets and paper wasps). Cicada Killer females use their sting to paralyze their prey (cicadas) rather than to defend their nests. Adults feed on flower nectar and other plant sap exudates.
Adults emerge in summer, beginning around July and continuing throughout the summer months. They are present in a given area for 60 to 75 days, until mid-September. They are commonly seen in late summer skimming around lawns, shrubs and trees searching for cicadas. There may be many individuals flying over a lawn, and females may share a burrow, digging their own nest cells off of the main tunnel. A burrow is 15 to 25 cm (6 - 10 in.) deep and about 3 cm (1.5 in.) wide. The female dislodges the soil with her jaws and pushes loose soil behind her as she backs out of the burrow using her hind legs, which are equipped with special spines. The excess soil pushed out of the burrow forms a mound with a trench in it at the burrow entrance. This ground-burrowing wasp may be found in well-drained, sandy soils to loose clay in bare or grass-covered banks, berms, hills as well as raised sidewalks, driveways and patio slabs. Cicada killers may nest in planters, window boxes, flower beds or under shrubs, ground cover, etc. Nests often are made in the full sun where vegetation is sparse, especially in well-drained soils.
After digging a nest chamber in her burrow, female cicada killers capture cicadas, paralyzing them with a sting; the cicadas then serve as food to rear their young. After paralyzing a cicada, the female wasp straddles it and takes off toward her burrow; this return flight to the burrow is difficult for the wasp because the cicada is twice her weight. After putting the cicada in the nest cess, the female deposits an egg on the cicada and colses the cell with dirt. Male eggs are laid on a single cicada but female eggs are given two or sometimes three cicadas; this is because the female wasp is twice as large as the male and must have more food. New nest cells are dug as necessary off of the main burrow tunnel and a single burrow may eventually have 10 to 20 cells. The egg hatches in one or two days, and the cicadas serve as food for the grub. The larvae complete their development in about 2 weeks. Overwintering occurs as a mature larva within an earth-coated cocoon. Pupation occurs in the nest cell in the spring and lasts 25 to 30 days. There is only one generation per year and no adults overwinter.
Interaction with Humans
Female Cicada Killer wasps are non-aggressive and rarely sting unless handled roughly, disturbed, or caught in clothing, etc. Males aggressively defend their perching areas on nesting sites against rival males but they have no sting. Although they appear to attack anything which moves near their territories, male cicada killers are actually investigating anything which might be a female cicada killer ready to mate. Such close inspection appears to many people to be an attack, but the wasps never land on people or try to sting or bite. If handled roughly females will sting and both sexes are well equipped to bite with their large jaws.
Source
An original version of this heavily-edited article was a copy of the fact sheet from the Ohio State University Extension.