The Harlequin Bug (also called Cabbage Bug) is found throughout most of the US In agricultural areas. It is in the Order Hemiptera or True Bugs. It feeds on the juices of cruciferous plants such as cabbage and on other plants such as beans and grapes. In our area it is found on members of the mustard family, telegraph weed, and in TPSNR especially on bladderpod.
One can find several bladderpods along the Guy Fleming and Beach Trails. These plants have yellow flowers and the seed pods look like two inch punching bags in need of pumping up. If one looks closely at the leaves, it may be possible to see harlequin bug eggs in tidy little rows. The bug hatches out of the egg looking a lot like the adult: shiny black with bright red patterns.
According to Hogue, in a laboratory environment the eggs hatch in 6 to 11 days, the nymphs undergo 5 moltings in 53 days, and the adults live 70 to 80 days. The bright patterns of red, white and black change with each molt.
Assuming the host plant is healthy, a Harlequin may spend its entire life on one plant. The adults have wings and can fly, but the typical defensive response of the bug when touched is to drop to the ground. It is very difficult to catch one of the bugs with your fingers. The only way is to put your hat under it and then touch it. The insect will then fall into your hat. After inspecting this or any other bug, it should be returned to its habitat.
The material here was excerpted from Notes from the Naturalist by Hank Nicol, May 15, 1980 and April 10, 1982, and Califomia Insects by Jerry A. Powell and Charles L. Hogue, University of California Press, 1979.
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