Endangered Species

Endangered Species

Mount Hermon June Beetle

Mount Hermon June Beetle

Scientific Name: Polyphylla barbata

Status: E

The Mt. Hermon June Beetle is a member of the family Scarabaeidae, a group containing dung beetles, rhinocerous beetles, and many other well-known insects. This beetle is found in the Santa Cruz Mountains south of the city of San Francisco. Endemic to less than 1500 acres. Most historic habitat lost.

Like most other scarab beetles, the Mt. Hermon June Beetle has soil-dwelling, grub-like larvae. This particular species prefers sandy soils. The Santa Cruz Mountains are largely volcanic in origin but there are scattered patches of soils derived from sedimentary sources (limestones and sandstone) which tend to be sandier. These patches, known locally as the "Zayante Sand Hills" formation, appear to be the primary, if not the only, habitat of this species.

The sandy habitat provides a different microclimate than is found elsewhere in the Santa Cruz Mountains; the soils tend to drain better and are thus drier, warmer, and more sparsely vegetated. In addition to Polyphylla barbata, the Zayante Sand Hills area supports threatened plants (Santa Cruz cypress, Silverleaf manzanita) as well as several other threatened insects, including the Zayante Band-Winged Grasshopper and the Santa Cruz Rain Beetle.

The primary threats to the species have been sand mining and urban development in general.

(photo courtesy of Zayante Sandhills Conservation Board)

To Learn More:

  • Essig Museum of Entymology
    Easy to understand information about California's endangered insects.
  • NatureServe Explorer
    Enter species name in the search box to access a detailed description, including habitat, behavior, food, current conservation status, ecological and distribution data with citations to relevant management reports.
  • U.S. Fish & Wildlife Service
    Documents describing protection for this species under the Endangered Species Act. General information about the species as well as plans both to protect it and to help it recover.
  • Species Account
    Excerpts from U.S. Fish and Wildlife Service documents available at the Central Branch Library