Thread subject: :: Mycetophilidae => Dziedzickia? No, Trichonta

Posted by Steve Scholnick on 20-02-2021 00:17

female fungus gnat found near the Potomac River. Keys out to Dziedzickia using the Manual of the Nearctic Diptera and in Shaw & Fisher's 1952 paper on "Fungivoridae". MND says "Dziedzickia is undoubtedly a complex of several genera." and the genus appears to include species with and without wing vein R2+3 (from Baxter, 1989: "The Nearctic species D. longicornis (Coquillett), D. polyzona (Loew), D. separata (Johannsen), and D. vittata (Coq.) differ from Hadroneura, D. marginata, and D. pentastylobia in the absence of vein R2+3." (https://www.jstor...e/25085060)). body length ~4mm

Not every character state in each MND couplet fits so I'd appreciate confirmation/correction of the ID. Thanks in advance for the help.


dorsal view of right wing; ventral view of left

Edited by Steve Scholnick on 20-02-2021 18:15

Posted by Paul Beuk on 20-02-2021 08:16

You misinterpreted the character of the arrangement of the microtrichia on the wing. In photo V at highest magnification you can see that the microtrichia are arranged in longitudinal lines near the tip of the wing. Once you have established that they key leads you straight to Trichonta. In most cases females are quite problematic to identify.

Posted by Steve Scholnick on 20-02-2021 18:17

Thanks Paul! I took the nice orderly lines of microtrichia in the MND figure too literally. Here's a crop of the right wing

(I'm not sure why I have so much trouble uploading photos to this site. Even a 145KB image named 1.jpg that's 600 pixels wide doesn't upload)

Edited by Steve Scholnick on 20-02-2021 18:28

Posted by Paul Beuk on 21-02-2021 10:05

It is even more distinctly visible in the more posterior part of the wing apex where the cell are broader.