Kelly’s Field Notes
Common Name: Cicada Killer
Genus: Sphecius (Greek for wasp)
Species: 21 species worldwide
Sphecius convallis - west coast USA species
Sphecius grandis - west coast USA species
Sphecius speciosus - eastern USa species
Sphecius antennatus - southern and eastern Europe
Most species in North Africa and Asia
Cicada killers are very large wasps, 3.8cm-5cm (1.5in-2in) in length. They are pretty loud flyers and can’t be missed with bright yellow and orange striping on their abdomens.They may aggregate together in tunnels near each other, but they do not live together or form hives or nests. They make tunnels near each other sometimes in the hundreds which can last for several years if undisturbed. Their tunnels look like very large ant hills, sometimes with sand or dirt flung wide around the opening.
Cicada killers emerge from their nests, males first, females after. Males will patrol areas, defending their territory while they wait for females. Females who have not mated yet will fly straight and slow, allowing a male to clasp onto her. If the female is flying in a zigzag pattern, she has already mated. Males may inspect her, but they won’t try to mate. After mating, the male dies and the female will dig a tunnel 15cm-25cm (6in-10in) underground in loose sand or soil, with each tunnel at a length of about 30cm-45cm (12in-18in), with branching cells to accommodate up to 16 larvae. This next part is where their name comes in. The female will leave the tunnels to find a cicada to paralyze and return to the newly dug cells.
Each cell will receive one to three cicadas, all on their backs, side by side, with their heads away from the opening. Males typically get one cicada while females get two or three (females are larger than males). She then lays one egg, regardless of how many cicadas are in the cell, behind the rear leg of the cicada. The eggs hatch within 24-36 hours. The larvae feed on the paralyzed cicadas, with one study mentioning after 82 hours (3.5 days) one had eaten the entirety of the cicada’s innards. Larvae burrow into the cicada and eat until they leave behind an empty husk.
After 96 hours (4 days) the larva will begin to spin a cocoon of fibers, held together with a substance coming from their mouths. The cocoons even have pores, presumably for respiration and humidity regulation. They overwinter in this state, then about a month before emerging as adults they pupate. Adults do not overwinter, but they do live fairly long at about 60-70 days. Adults feed on nectar and other sugary substances.
Cicada killer males are stingless, as with all Hymenopterans. The female packs a punch though, with venom used to paralyze cicadas. On The Schmidt Sting Pain Index cicada killers are only a level 0.5. Justin Scmidt even goes so far as to call them “gentle giants of the wasp world.”
Paralysis - females use their stingers to paralyze cicadas
Flight - what’s a wasp without wings? We’ll cover those another time.
Efficiency - cicada killer females can catch over 30 cicadas during their lifetime (they catch annual cicadas not brood year cicadas)
Strength - carrying a cicada that is twice as heavy as they are, cicada killers are strong ladies!
Sneaky - sometimes females will sneak into the tunnels of other females and lay their eggs on the stashed cicada.
Docile - because cicada killers are solitary they are less likely to sting humans, if she dies in a fight the ancestry stops with her.
Wasps: The Astonishing Diversity of a Misunderstood Insect by Eric R. Eaton
Sting of the Wild by Justin Schmidt
“Cicada Killer Wasps | Entomology.” Entomology at the University of Kentucky, entomology.ca.uky.edu/ef004.
Coelho, J. R., Charles W. Holliday, and J. M. Hastings. "Intra-and interspecific prey theft in cicada killers (Hymenoptera: Apoidea: Sphecius)." Journal of Insect Science 19.1 (2019): 13.
Dambach, Charles A., and Eugene E. Good. "Life history and habits of the cicada killer in Ohio." (1943).
Entomology, Purdue Extension. “Cicada Killers.” Extension.entm.purdue.edu, extension.entm.purdue.edu/publications/E-254/E-254.html.
Lin, Norman. "The weight of cicada killer wasps, Sphecius speciosus, and the weight of their prey." Journal of the Washington Academy of Sciences (1979): 159-163.