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Fall Fund Drive

Thick-headed Fly - Physoconops obscuripennis - female

Thick-headed Fly - Physoconops obscuripennis - Female
Atco, Camden County, New Jersey, USA
June 4, 2012

Images of this individual: tag all
Thick-headed Fly - Physoconops obscuripennis - female Thick-headed Fly - Physoconops obscuripennis - female Thick-headed Fly - Physoconops obscuripennis - female

Moved from Physoconops.

Keys unambiguously to P. obscuripennis in Williston's key here and is in excellent agreement with his detailed description here. Also keys to same species in Camras (1955), though with some ambiguity at couplet 41, i.e. "1st poterior cell hyaline vs. darkened". The 1st posterior cell in the image here is hyaline, which would lead to P. discalis, which is a strictly western (and south to Mexico and beyond) species. Following the alternate choice leads (via 43a "front and vertex entirely dark", and 44a "wing pattern diffuse") to P. obscuripennis. The excellent agreement here with Williston's description suggests the key of Camras may be in error at its couplet 41 (that is, variation in the degree of subtle infuscation of the discal cell in obscuripennis may not always conform to Camras' "1st posterior cell darkened" condition).

The entirely black frons and vertex; and 3rd antennal segment about half the length of the 2nd...together with the wing pattern and overall body coloration...are strong indicators for P. obscuripennis.

Also note the very large theca in the 2nd image of the post, indicating a female here.

This is Physoconops
Moved from Physocephala marginata.

Note the crossvein r-m on the wing at right is less than half-way out along the length of the discal cell. Also, the hind femora have uniform thickness, rather than having basal half noticeably thickened. See here for more details.

Moved from Conopinae.

Physocephala marginata
Physocephala marginata

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