This week’s subject is the rose weevil. Weevils are beetles with exaggerated snouts. The snout, or rostrum, helps the insect munch into its favorite foliage to lay eggs and to eat. Weevils are vegetarians. 

The chewing mouthparts are only at the tip of the weevil’s rostrum (the mouth doesn’t open wide like an alligator), and antennae sprout from somewhere along its Pinocchio-worthy length. I think the combination makes weevils look like the lovable clowns of the beetle order. 

The rose weevil is quite common on wild roses at Mount Pisgah. If you see one, try looking for more. It’s a good bet that your eyes will start picking them out. A warning: if you get too close too fast, they’re known to deliberately fall to the ground. 

There are two species of these striking red and black beetles on the west coast. One, Merhynchites bicolor, lays eggs in, and larvae grow up in, the rose hips. The other, Merhynchites wickhami, has larvae that develop in the buds. The weevil above is boring a hole in the bud, so I’m guessing it’s the wickhami, or western rose weevil, species. 

It looks to me like the males are about the same size as the females, but may have slightly shorter snouts. That would make sense, as they don’t do the egg-laying. In fact, in some weevils, the male’s proboscis is half the length of the female’s. 


Stay curious!

Sources:

The Bug Lady: https://uwm.edu/field-station/green-weevil-red-weevil/

BugGuide.net for pictures and other info: https://bugguide.net/node/view/30858