HPIPM:Sumac Flea Beetles
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Compiled by Whitney Cranshaw, Colorado State University:
Colorado Insects of Interest
Sumac Flea Beetles
Scientific Name: Blepharida rhois (Forster)
Order: Coleoptera (Beetles)
Family/Subfamily: Chrysomelidae (Leaf Beetles)/Alticinae (Flea Beetles)
Identification and Descriptive Features: The adults are moderate sized beetles capable of jumping by use of well developed hind legs. The wing covers are cream colored with irregular, wavy reddish markings. The prothorax is orange.
Larvae are grayish, with a cylindrical body form. They are slightly shiny and carry on their back dark particles of their feces.
Distribution in Colorado: Widely distributed in association with their host plant, skunkbrush sumac (Rhus trilobata).
Life History and Habits: Overwintered adult beetles move to skunkbrush sumac in spring shortly after bud break. They feed on the emerging growth and females then lay eggs in small masses on the twigs, which they cover with a paste of excrement.
The larvae feed on the new growth, usually in small groups. Chewing injuries produce ragged leaf wounds and when larvae are in high populations they may heavily defoliate plants. Peak feeding typically occurs during late May and early June, with full-grown larvae then crawling to the soil to pupate. Adults emerge by early summer and feed on leaves through September before moving to sheltered areas in winter. A single generation is thought to occur.
Sumac flea beetle larvae protect themselves with “shield defenses” using their feces that they pile on their back, often near the head end. These contain toxins derived from their sumac host and this defense protects them well from ants and many other potential predators. The covering fecal shields produced by the mother also protect the eggs.
Species of Similar Appearance: Some leaf beetles of the genus Calligrapha have the approximate size and shape of the sumac flea beetle. Among the more common species that are present in Colorado are Calligrapha multipunctata (Say), associated with willow, and Calligrapha lunata (Fabricius), associated with Rosa. Plants of the genera Ambrosia, Coreopsis, and Bidens host Calligrapha californica coreopsivora Brown and C. bidenticola Brown. Patternings on the back and their inability to jump can distinguish these from sumac flea beetle.
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