Yellow Legged Fly from Belize is Timber Fly

Subject: It’s THE FLY!!
Location: Toledo District, Belize
December 19, 2014 1:19 pm
Howdy, fellow bug fans,
I took this photo just before Halloween, but never had good enough internet to get it off for your help in ID’ing it. I’d never seen one before and haven’t seen one since.
Pretty cool.
Signature: Tanya

Probably Robber Fly
Timber Fly

Dear Tanya,
This fly sure looks predatory, which makes us speculate it is probably in the family Asilidae, the Robber Flies and Deer Flies.  It really resembles this image of a Timber Fly,
Pantophthalmus cf. pictus from Costa Rica that is posted to Piotr Naskrecki’s The Smaller Majority website.  According to Piotr:  “Timber flies are a small family, consisting of only 2 genera and 22 species, all found in the lowland rainforests of Central and South America. In addition to their unholy size they differ from other flies in that their larvae are wood burrowers, something that traditionally has been the domain of longhorns and other beetles. There are other flies that feed on wood (some Syrphidae and Asilidae), but those are incapable of drilling their own tunnels in the wood and can only use those already created by beetles or other insects.  Little is known about the behavior of adult timber flies. Nobody is really sure if they feed at this stage, and if so, on what. They have never been seen mating, although oviposition has been observed. Females have a long, telescopic ovipositor, which they use to deposit eggs in the cracks of dead and live wood, depending on the species. These insects are not common.”  This is only the third Timber Fly we have posted to our site.  We will try to contact Piotr to verify that identification.

Probably Robber Fly
Timber Fly

Piotr Naskrecki confirms genus identification
Hi Daniel,
Yes, it is definitely Pantophthalmus, and it does look similar to pictus.

Thanks, Daniel,
We live in a heavily forested area in Belize, so this ID makes lots of sense.  It’s great to keep discovering new-to-us life forms in a place where we’ve lived for a long time.

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