Aphthona nigriscutis explained

Aphthona nigriscutis is a root-feeding flea beetle of the genus Aphthona. It is one of five Aphthona spp. that has been used in Alberta, Canada to control leafy spurge, an invasive plant that reduces pasture quality and degrades natural habitats.^[1] It, along with A. lacertosa, is one of only two biocontrol agents thought to be effective against leafy spurge.

Larvae cause the most damage to the plant by feeding on the roots.^[2]

Nontarget impacts

A. nigriscutis will feed on the native Euphorbia robusta Engelm, though this is thought to be acceptable as the weevil significantly reduces leafy spurge populations over time.^[3]

Return of diversity following biocontrol

A 14-year study documented a slight increase plant species richness in a Montana grassland system after release of A. nigriscutis to control leafy spurge.^[4]

Notes and References

1. Bourchier, R., Erb, S., McClay, A, and Gassman, A. 2001. Euphorbia esula (L.) (Leafy spurge) and Euphorbia cyparissias (L.) (Cypress Spurge) (Ephorbiaceae). In Mason, P. and Huber, S. (Eds). Biological control programmes against insects and weeds in Canada 1981-2000. CABI Publishing, Wallingford, UK.
2. Web site: Density and efficacy of the flea beetle Aphthona lacertosa (Rosenhauer), an introduced biocontrol agent for leafy spurge, in Alberta. Andrea Ruth Kalischuk. May 2001 . University of Lethbridge.
3. Feeding Impacts of a Leafy Spurge (Euphorbia Esula) Biological Control Agent on a Native Plant, Euphorbia Robusta. John L. Baker and Nancy A. P. Webber. Invasive Plant Science and Management. 2008. 1. 26–30. Invasive Plant Science and Management 1(1):26-30. 2008. 10.1614/IPSM-07-018.1. 86092372.
4. Effect of Biological Control on Leafy Spurge (Euphorbia esula) and Diversity of Associated Grasslands Over 14 Years. Peter Lesica and Dave Hanna. Invasive Plant Science and Management. 2009. 2. 2. 151–157. Invasive Plant Science and Management 2(2):151-157. 2009. 10.1614/IPSM-08-128.1. 85934540.