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Species Arilus cristatus - North American Wheel Bug

Hatchlings - Arilus cristatus Wheel Bugs? - Arilus cristatus - male - female Squash Bug or Assassin Bug Nymph - Arilus cristatus Young Assassin Bug - Arilus cristatus Bug 0969 - Arilus cristatus Gray Insect - Arilus cristatus Florida WheelBug - Arilus cristatus Wheel Bug - Arilus cristatus - male Acanthocephala? - Arilus cristatus Wheel Bug - Arilus cristatus assasin bug? - Arilus cristatus Wheel Bug - Arilus cristatus
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder Heteroptera (True Bugs)
Infraorder Cimicomorpha
Family Reduviidae (Assassin Bugs)
Subfamily Harpactorinae
Tribe Harpactorini
Genus Arilus (Wheel Bugs)
Species cristatus (North American Wheel Bug)
Other Common Names
Wheel Bug (also applies to the rest of the genus)
Explanation of Names
Arilus cristatus (Linnaeus 1763)
cristatus (L) 'crested'
The common name derives from the cog-like projection on the back of the adult
Size
at 28-36 mm (females larger than males), our largest assassin bug(1)
Identification
The "cogwheel" on the adult's back is unmistakable
Range
e NA (ON-FL to IA-KS-NM-CA) to C. Amer. - Map (2)(Hagerty & McPherson 2000)(3)
Habitat
Found where prey is abundant: adults often lurk on composite flowers attractive to insects, or prowl in trees where caterpillars are plentiful
Season
Nymphs hatch in spring, adults are found late spring into fall and early winter
Food
All stages prey on other insects (caterpillars, aphids, bees, sawflies, etc.)
Life Cycle
One generation per year. Adults mate in fall, the male then guards the female
since other males may try to move in .
Clusters of eggs (described as "brown bottles with fancy stoppers") are laid in hexagonal clusters on trees, shrubs or other structures, generally within 4 feet of the ground

Eggs hatch in spring:

Nymphs face predation and cannibalism
(about 3 months to maturity): red/black

red/grey

grey/black
.
They hunt down their prey such as this one walking on a Hyphantria tent
and attack
.
Molting:

Which can be fatal if they can't extricate themselves:
and leave behind just an empty shell, inverted tracheal tubes and all
Adults are generally not seen until May even in warmest parts of the US and may survive into December
Some are unfortunate victims of parasitoids despite chemical defenses
Others thrive, sometimes even with deformed wheels
Print References
Hagerty A.M., McPherson J.E. (2000) Life history and laboratory rearing of Arilus cristatus (Heteroptera: Reduviidae) in Southern Illinois. Fla. Entomol. 83: 58-63. (Full text)
Internet References
Featured Creatures (Mead 2014)(4)
Works Cited
1.How to Know the True Bugs
Slater, James A., and Baranowski, Richard M. 1978. Wm. C. Brown Company.
2.The Reduviidae (Hemiptera: Heteroptera) of Alabama, with a morphological key to species
Clem C.S., Swanson D.R., Ray C.H. 2019. Zootaxa 4688: 151–198.
3.Global Biodiversity Information Facility (GBIF)
4.University of Florida: Featured Creatures