Friday, April 6, 2012

Eyed Click Beetle

On my last expedition into southern Ohio's Shawnee State Forest, I stumbled into a variety of interesting beetles, such as this diminutive two-lined leatherwing, Atalantycha bilineata. If you are familiar with bluets - the wildflower that the beetle is nectaring at - you'll know how small this little flower beetle is. Two-lined leatherwings are said to be very common in early spring in these parts.

This rather horrifying looking beetle was much larger than the leatherwing - at least a half-inch in length. I spotted it from some distance as it slowly clambered about some rocks. It is an oil beetle, Meloe angusticollis (at least I think that it is this species). Its common name stems from its ability to discharge caustic chemicals from glands in its legs as a defensive tactic. The strange kinked antennae are used to grab and hold the female during mating. A bit of an ogre, this one.

I tend to be a habitual log-turner, as you never know what might be hiding below. I spied this rather small and ordinary piece of woody flotsam lying on a stump, and gently turned it in the hopes that a copperhead or ring-necked snake might be underneath.

To my great satisfaction, there were two adult horned passalus beetles, Odontotaenius disjunctus, lurking in the punky wood. These big bugs are sometimes called patent leather beetles, and the carapace does indeed resemble freshly shined dress shoes.

As I manipulated the wood to get better angles of the horned passalus, I was delighted to spot this alien-looking insect crammed in a crevice, apparently still in a hibernatory stupor. Eyed click beetle, Alaus oculatus! I don't think they are particularly rare, but it was only about the fourth one that I've come across.

Eyed click beetles are pretty good-sized, nearly two inches in length. We found the one above on another foray into Shawnee back in 2010. It is posed on the leaf of an aspen, and is playing dead. If the scary fake eye spots don't deter a would-be predator from messing with it, the beetle tucks its legs in, stiffens up, and acts dead.

Of course, if the click beetle is on wood, chances are you won't notice it. They blend amazingly well with their surroundings. Someone found the above beetle back in 2009 on the Magee Marsh bird trail, and we posed it on the boardwalk's wooden rail. Eyed click beetles live in and around rotting wood, as the immature grubs are predacious and feed on the grubs of wood-boring beetle species such as the horned passalus in the previous photo.


Click beetles get their name from their ability to suddenly snap themselves explosively into the air. The beetle has a stiff rodlike structure under its body that slots into a groove, and can be held under pressure. When nudged and prodded, it'll suddenly pop that rod loose and flip into the air like a six-legged tiddlywink. Click the video above for a demonstration. I imagine if the harasser were a chickadee or some other small bird, and this spooky big-eyed bug suddenly snapped into its face, the bird would hotfoot it out of there.


DebM said...

Just got back from the Upper Texas Coast and had one of these at Sabine Woods. Thanks to your blog I knew what it was! It was buzzing around us--huge and noisy--and I knew I had never seen it before. Then it landed and we got pictures of both top and bottom--so exciting.

Jim McCormac said...

I'm glad the blog was helpful to you, Deb, and sounds as if you and the beetle really clicked!

Anonymous said...

That big eye spot beetle was cool. Mom found one when we were backing out of the gargage to the local garden store. We stumped them. They couldn't identify the beetle. Thanks to your web page we found out what it was and let it go.

Anonymous said...

I saw one on my wooden deck patio! I snapped a picture of it and trying to keep my Cat from nailing it it flipped over and I managed to get a picture of it's underside