134: Pleasing Fungus Beetle

Species: Gibbifer californicus

Pleasing Fungus Beetles are a family of beetles, Erotylidae, with over 100 genera. They are characterized by eating plants and fungal matter, and the oldest known are from the Early Cretaceous, having been found in amber in Lebanon. One species of Erotylidae act as pollinators for cycads.

In Colorado, we have a particularly distinctive species of this family, Gibbifer californicus, which has a dark head and a blue or purple wing covers with black spots. This species lives in aspen and pine forests throughout the state. They are large for a beetle, about 2.5-3cm (1”) long. They start their lives as larvae living in and feeding on fungus on ponderosa pine or aspen trunks in spring to early summer. After that, they hang from the underside of logs – much like a bat colony – and transform into pupa. A few weeks pass before they emerge as fully grown adults, when they are active until the early fall, with a single generation being produced each year. I have never seen these but will keep an eye out for them the next time I am in an aspen forest in summer!