Ten-lined June Beetle: Polyphylla decemlineata



Ten-lined June Beetles are abundant throughout the San Dieguito River Park.
They begin to emerge as adults around early to mid-June; thus the name. These insects are one of the more beautiful of the San Diego County beetles, with their bold alternate striping, and large size. They fly to lights readily and so are commonly seen by homeowners and campers after dark. They are harmless to humans, but will sometimes make a squeaking sound when picked up. They remain active throughout the summer and mate and lay eggs before the cold weather sets in. The males have large expandable antennae for detection of pheromones from the female. The larvae feed and pupate in the soil.

Text and Photo by Robyn Waayers. Robyn has been a resident of San Diego County since 1977, and is a biology instructor at Palomar, Miramar and Southwestern Colleges, and is also a freelance nature photographer. Contact information: rwaayers@aol.com

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