Friday, June 29, 2012

June bugs

What: Just in time for the end of June, I heard this June bug (Polyphylla sp., poly = many + phylla = leaf referring to the many "leaves" that fork out at the tips of its antennae) before I spotted it. I finally found it tucked into the ground, head up, butt half in. When I rediscovered the same individual it was again nearly vertical, but this time more submerged with its abdomen in the ground and head barely above. The beetle itself is rather large, about an inch long and almost half that around. Its elytra (hard coverings beetles have over wings) were a dullish brown with irregular speckling that seemed more from wear and tear than genetic programming. When it made its noise, it sounded more like a wounded baby mouse than an insect. It made the sound in response to my footsteps and when provoked (i.e. poked with a blade of grass) it repeated the noise. Seems like an odd defense, and made me wonder what other defenses it had to back up the aggressive noise. A little research unearthed some anecdotes of pets going after these large insects then requiring vet visits for swollen faces. So the sound must be some sort of deterrent rather than mate attractant.

I watched the beetle to figure out how it made the noise and it appears as though it makes it by puffing out its abdomen and then sucking it back in, rubbing the top of it against its wings as it does to make a scratchy noise. Pretty wild.

Ecological notes: Males have very robust enlarged feathers on their antennae for picking up whifs of the female pheromones. This one, with much smaller antennae was most certainly a female. Most of the beetle's life cycle is spent underground as large white larvae with yellowish to orange heads - hard to miss. The females lay their eggs in the soil, which makes me wonder if the defensive posturing of the female was her actually defending her egg-laying territory from an intruder (me).

Where: My backyard (maybe yours too?)

Other notes: Heard my first cicada of the year today!

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