Flower Longhorn: properly identified as Lion Beetle

winged nonflying long antennaed, solitary
August 3, 2009
This creature appeared by itself just beyond the edge of a wooden porch deck. It wasn’t looking very chipper–moving slowly, stumbling, crawling on leaves–so I offered it water and then honeywater in a saucer (which I feed troubled bees). It drank a little and then lost balance in the water and fell to the ground.
Not to worry, though, it went under the deck and emerged on the other side–twice–walking, not flying. This would be a total of around 16 feet of wandering.
I found it again about an hour after first spotting it, and it was on the steps kinda floundering, not totally upright and seemingly waving a few legs to get my attention, so I offered my finger and it rode on my hand while I got the camera.

Deformed Cosmosalia chrysocoma?
Lion Beetle

This all happened yesterday, I haven’t spotted it today.
I hope the photos show it well. What really got our attention were the exceptionally long articulated antennae, long body and tail that the insect curved up from time to time, and short wings.
In one picture, you can see the second set of legs up in the air like a surrender or a show of ferocity.
Juliette Sterner
Olympic Peninsula Washington

Deformed Cosmosalia chrysocoma?
Lion Beetle

Hi Juliette,
We have a guess for you, and we are going to request assistance from Eric Eaton to confirm or deny.  This is a Long Horned Borer Beetle or Longicorn in the family Cerambycidae.  Additionally, we believe it is one of the Flower Longhorns in the subfamily Lepturinae.  We believe we have identified it as Cosmosalia chrysocoma, a species with no common name.  According to BugGuide it can be identified by:  “The very dense, appressed, metallic golden pubescence is quite distinctive.
The puzzling component of your photo is what appears to be a deformation of the elytra or wing covers.  We aren’t sure if it is a natural deformation, or caused by trauma, or if perhaps they haven’t fully expanded due to recent metamorphosis.  We hope Eric Eaton can shed some light on this.

Deformed Cosmosalia chrysocoma?
Lion Beetle

Comment with Correction
I don’t know North America longhorns but I’m sure that you identified it wrong because if the second par of wings is unharmed so I tried to identify it myself and I found that it might be a Lion Beetle – Ulochaetes leoninus at least according to bugguide http://bugguide.net/node/view/65020/bgimage.

Thanks mardikavana,
We appreciate the correction.  Seems it must not be such a common beetle if there is only one image on Bugguide.  We decided to do a bit more web snooping and Answers.com indicates:  “
DISTRIBUTION  Pacific coast, from British Columbia to southern California.
HABITAT  Pine forests.
BEHAVIOR  Look, sound, and behave like bumble bees.
FEEDING ECOLOGY AND DIET  Larvae bore into sapwood of conifers.
REPRODUCTIVE BIOLOGY  Eggs are laid at the base of standing dead trees and stumps.
SIGNIFICANCE TO HUMANS  Interesting example of physical and behavioral mimicry.

Update from Eric Eaton
August 4, 2009
Hi, Daniel:
I agree with the identifications for both of the beetles:  A species of Derobrachus, and an example of the “lion beetle” as offered by others.  See what a great community you have created?:-)  I tell you, I learn as much from WTB as I contribute….
… Keep up the great job, Daniel:-)

4 thoughts on “Flower Longhorn: properly identified as Lion Beetle”

  1. Why hasn’t anyone commented about how wonderfully this beetle mimics a wasp? The thorax covered with yellowish hairs, the legs alternating black and yellow, the hind legs longer than the other 4, and above all the small elytra exposing fully extended underwings. Other longhorn beetles have full length elytra, which cover folded up underwings. This one has underwings that look like those of wasps. If you find one on a flower the off the cuff conclusion is “Wasp! Caution!”. Nature is so absolutely wonderful.


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