Numbers
In North America, this is the only species in the genus.
Identification
Both markings and color are variable, but generally includes a variably-shaped dark central band running from the head toward the rear of the insect. The pale area on the right and left sides of the pronotum contain one to three dark spots (usually two). The dark color is dark blue to black. The light color may be white, pink, yellow, orange, or red.
Nymph is all black or black with a red spot.
Boris Buche offers this tip to distinguish this genus from genus
Zicrona: Profemora with strong tooth (without tooth in Zicrona).
Range
Eastern United States and Great Plains.
Habitat
Found on a wide variety of herbaceous plants.
Season
Adults may be found throughout the late Spring, Summer, and early Fall. April-September (North Carolina).
Food
Adults feed on the larvae of beetles, butterflies, and moths. Stiretrus anchorago is considered an economically beneficial insect, feeding on the larvae of the Mexican Bean Beetle, among other pest species.
Life Cycle
Eggs typically take seven days to hatch. The progression through the five instars takes another 25-35 days.
Remarks
A handsome species that comes in a variety of color forms. There is only one North American species recognized in this genus. In 1971 two entomologists proposed a new species, Stiretrus fimbriatus, but others believed the proposed species was simply a color variant of S. anchorago.
See Also
Zicrona caerulea resembles the all-black or all-blue forms, but and the absence of a strong tooth on the profemora (frontmost "thigh") distinguish it from Stiretrus.
Print References
Slater, p. 42, fig. 49
(1)
Swan and Papp, p. 129, fig. 126
(2)
Salsbury, p. 96--photo
(3)