Scarab Beetles

There were three species of scarab beetles (koganemushi) in the park today.


Order: Coleoptera; Family: Scarabaeidae
Subfamily: Cetoniinae
kanabun = Rhomborrhina japonica

Order: Coleoptera; Family: Scarabaeidae
Subfamily: Rutelinae (Shining Leaf Chafers)
mamekogane = Popillia japonica
semadarakogane = Blitopertha orientalis

The kanabun was on a small oak tree, feeding on tree sap that was leaking from a cut. It’s a pretty big beetle (about 25mm) and it’s quite common here in the summer – crashing into lighted windows at night usually!! This one flew away really fast when I disturbed it. I wanted to take a better picture but I couldn’t this time.

The smaller (10-12mm) mamekogane is present in huge numbers. They are everywhere! And they eat the leaves of many different plants – destroying many of Shinobu’s garden plants (especially the roses) much to her annoyance. In America, where this insect is a pest, it is called a “Japanese Beetle.” Here is some more information about this species: Ministry of Agriculture (British Columbia).

The small (8-13mm) semadarakogane is also pretty common, but nowhere near as common as mamekogane. It also has great potential as a pest species, and so appears on notification lists in various countries.