Pretty green beetle…
May 2, 2010
Pretty green beetle…
…but of course, if one googles “green beetle,” one gets a million images of ugly Volkswagons. I just found this beetle today (May 2) in my back yard in Newton, New Jersey. It is on lemon balm, a plant in the mint family.
Jeannie
Newton, northwestern New Jersey
Hi Jeannie,
Your pretty green beetle is a Thistle Tortoise Beetle, Cassida rubiginosa. According to BugGuide it is also called a Bloody Nosed Beetle which “supposedly refers to the beetle’s ability to secrete a reddish liquid from its head, giving rise to its other common name.” BugGuide also indicates the Thistle Tortoise Beetle was accidentally introduced to Canada in the early twentieth century from Eurasia and it has since spread south to the eastern U.S. Because it feeds upon some introduced thistles and other nonnative weeds, the Thistle Tortoise Beetle was intentionally introduced to Virginia where, according to Bugguide, it “has been used in biological control of thistles. It can reduce thistle vigor and survival, particularly in vigorous grass, but its impact is usually restricted by parasitoids.”