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Photo#495211
Small-headed Fly - Ogcodes - female

Small-headed Fly - Ogcodes - Female
Maryville, Nodaway County, Missouri, USA
June 11, 2010
Size: ~5mm
She is shown here laying eggs, must have thought the string was from a large spider.

Images of this individual: tag all
Small-headed Fly - Ogcodes - female Small-headed Fly - Ogcodes - female

Moved
Moved from Small-headed Flies.

Definitely Ogcodes
For those who may be interested, below are details of how I got Ogcodes, and formulated a tentative species ID of O. eugonatus. If someone knowledgeable (e.g. Dennis) concurs, we can move the images there.
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First, from the photo, this keys clearly to Ogcodes in the Manual of Nearctic Diptera(1) via these characters: lack of apical spines on tibiae; antennae attached on ventral part of head; flagellum short, rod-like (look closely and you can see the antenna tip against the background of the left fore-femur).

It also has the bulky gestalt, distinctive wing venation, and (thin here) white bands at the posterior margins of the tergites of Ogcodes.

Next, I tried to get to species using the four references on the Ogcodes info page. In the last three, the keys require one to decide whether wing vein M1 is present or absent. I think it's absent...but I can't tell for sure from the photo, so I went both ways. Also, between Cole's 1919 treatment and the 1960 treatment of Schlinger, the taxonomic groupings got subtly shifted around and/or synonymized, then re-separated, etc. The details are complicated, and one has to read the remarks in the descriptions in each reference to try to clarify things...but I'll just mention the bare bones milestones and my conclusion.

Using the key on pg. 61 of Cole (1919), I got down to candidates O. niger or O. pallidipennis.
Using the key on pg. 338 of Sabrosky (1944) I got to O. pallidipennis or O. eugonatus.
Using the key on pg. 410 of Sabrosky (1948) I got to O. borealis or O. eugonatus.
Using the key on pg. 274 of Schlinger (1960) I got to O. niger or O. eugonatus.

Correlating the descriptions in the references, O. niger is very unlikely, as it's only known from 1 female specimen from Utah. Also, the descriptions of the leg colors really only fit for O. eugonatus. Finally, compare the fly here with the MCZ type images for the four candidate taxa above: O. niger, O. pallidipennis, O. borealis, and O. eugonatus

O. eugonatus appears to be an excellent fit in terms of the overall "super-bulky" shape, the body & leg coloration, and (what's left of) the vestiture (since 1872!:-). The other candidate's images don't fit so well. Also note that, regarding the wider white tergal bands on the MCZ specimen vs. the fly in the post here...Sabrosky emphasizes that throughout the genus, these bands are typically much wider on males than on females. I'm guessing the MCZ type image for O. eugonatus shows a male, which would account for the discrepancy between the wider white tergal bands there compared to our egg-laying female here.

 
Thank you for your labors!
Apologies for not responding sooner. You certainly poured over the books to come up with a strong case for O.eugonatus! I'm glad there is a chance that not all her young were wasted on a string. If you ever want me to return the favor and help on some photos you have, don't hesitate to get a hold of me. Again, thanks for making this website such an outstanding resource.

Were the black specks her eggs?
Pity if so, would be a waste of much of her life's effort!

But there are so many both below and above her...maybe those black dots are something else?

 
Revisiting...after finding some references.
Upon studying Schlinger (1987) and Cole (1919) [see "Print References" at bottom of Acroceridae info page] I was surprised to read that in Acroceridae "...females lay up to 5000 eggs soon after mating...", and that in the genus Ogcodes "The smallest twigs were regularly covered with black dots in rows . . . the pear-shaped eggs colored deep blackish brown and fastened tight to the twigs by the small end..."

Thus those black dots might represent as little as 1/100 of all her eggs...so I guess her life's effort wouldn't necessarily be wasted if nothing came of them.

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