Any of various large usually brown North American leaf-eating beetles common in late spring; the larvae feed on roots of grasses etc. WordNet 3.0 & Open English WordNet

Phyllophaga is a very large genus of New World scarab beetles in the subfamily Melolonthinae. Wikipedia

June beetle is the common name for several scarab beetles that appear around June in temperate parts of North America: In subfamily Cetoniinae: Cotinis nitida of the southeastern United States Cotinis mutabilis of the western and southwestern United StatesIn subfamily Melolonthinae: Amphimallon solstitiale of Europe Melolontha of Europe Phyllophaga of the Americas Polyphylla decemlineata of the western United States and Canada. Wikipedia

A genus of beetles in the subfamily Melolonthinae of the family Scarabaeidae, also known as June bugs or June beetles Wikipedia Disambiguation

Any of several scarab beetles that appear around June in temperate parts of North America. Wiktionary

Scarab beetle. Wiktionary (translation)

The ten-lined June beetle (Polyphylla decemlineata), of the western United States and Canada. Wiktionary