Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Photo#15959
wasp-parasitized rove larva - Exallonyx

wasp-parasitized rove larva - Exallonyx
Derry, Rockingham County, New Hampshire, USA
This staphylinid larva was uncharacteristically sluggish, which was understandable when I found its expired husk in the rearing container with this scene of emergence from the movie "Alien."

Images of this individual: tag all
wasp-parasitized rove larva - Exallonyx wasp-parasitized rove larva - Exallonyx

Moved
Moved from Proctotrupids.

 
With a handle like "proctos"
I'm guessing he/she is probably an expert, but do you know who this is?

 
Hi Jim
Have you seen the new feature where editors can see contributor's comments? Using that I can see Proctor has been around since June of 2007. I'd say he/she's trustworthy.

Proctor - if you you're reading this... please consider filling out your account information to let people know your area of expertise and experience. Thanks!

 
Thanks, Lynette.
I hadn't noticed that new feature.

 
oops
I meant Proctos... not Proctor. Sorry about that.

Exallonyx sp. pupae
Exallonyx sp. pupae

Moved
Moved from Rove Beetles.

parasitoids i think are in th
parasitoids i think are in the genus exallonyx in the family procotrupidae

 
Why do you think so?
Do they specialize in rove beetles?

 
Proctotrupidae
I can't speak to the genus, but I have these notes on Proctotrupidae: "mainly endoparasites of beetle larvae, solitary or gregarious... generally those inhabiting leaf litter such as Carabidae, Staphylinidae, and Elateridae... Phaenoserphus viator lays eggs in Pterostichus ground beetle larva; when larva approaches maximum size, the 30 or so larvae feed rapidly, destroy host, and then each makes its own hole in the integument of the host’s ventral surface, and crawls out for about ¾ of its length, leaving only its posterior end anchored; they pupate without forming a cocoon, and all of the pupae are oriented with their heads oriented toward’s the host larva’s anterior end." An illustration of this in Askew closely resembles the scene you've captured here.
All of this seems like a perfect match for these pupae, and it seems to me that these images would be a good addition to the (almost non-existent!) section for that family.

 
More info
I just stumbled on Taro's blog here, which has a lot of similar photos.

 
Thanks, Charley.
I wonder why Taro didn't steer me to his work. Fascinating stuff.

this is very interesting, the
this is very interesting, there is very little literature on the parasitization of staphs. do you by any chance know what family the parasitoids were?

 
Alas, no.
These pupae all died. Too much handling maybe.

Wow
Amazing photo.