Found flying around indoors. At one point it actually dive-bombed into my ear(!)...but then quickly flew out and landed on the ground nearby, where it sat and seemed to stare at me for many minutes.
The dorso-ventrally flattened form and pointy mouth-parts made me think Hippoboscidae, and the wing venation seemed unusual. Using the MND
(1), together with a microscope, I was able to key it to genus
Pseudolynchia. Salient key characters:
* Conspicuously projecting conical lobes on each "shoulder";* Antennae much shorter than palpi (= visible portion of mouthparts here);* Scutellum with a pair of strong preapical bristles; and anterolateral processes of face strongly divergent, markedly longer than face proper;* Wing with only crossvein r-m present (crossvein dm-cu absent); and* Hind margin of scutellum straight or nearly so, sharply edged, with a transverse series of setigerous tubercles near each posterior corner.
Moreover, I was able to find a detailed 1966 reference by Maa (see
info page) and with the info there and study of the specimen under a microscope, I determined that this is
Ps. canariensis...a species introduced from Europe, most commonly found on domestic pigeons, but also afflicting a large number of other bird taxa. Crows (
Corvus) and among the many birds listed as hosts in Maa, and they were very abundant in the locale here (pigeons were not present).
There are just 4 species of
Pseudolynchia worldwide, and only two in the nearctic. For a while I thought this might be the native nearctic species,
Ps. brunnea, because while scrutinizing the images of wing venation in Fig. 18 on pg 135 of Maa (1966), I noticed that
brunnea was the only species shown with crossvein rm occuring distal to the point where the subcostal vein met the anterior wing margin...and that is the case for my specimen. But there was no mention of this character in Maa's detailed paper.
Then I noticed Maa's paper gives the range of
Ps. brunnea as mostly eastern...from New York to Ontario and Minnesota, down to Texas and Florida. Moreover, the wing length here is 6.6mm, which falls within the range of
Ps. canariensis (4.5-7.5mm), rather than that of
Ps. brunnea (4.8-6mm). And the pattern of "microtrichia" on the wing surface corresponds to that of
Ps. caraniensis as well. It took me a while to figure out what exactly the term microtrichia referred to. From the word roots I figured it meant "microscopic hairs"...and they
are truly microscopic...I could only barely see them at 40x magnification and pin-sharp focal adjustment under the dissecting scope. The patterns of the microtrichia (or setulae) are conveyed by "stippling" in figures 11-14 on pg 1276 of the MND
(1). I could not get an image capturing that degree of detail with my camera equipment.
Finally, I tried to determine whether this is a male or female. Maa (1966) states that males can be distinguished by 3-7 peg-like spines on the ventral side of the basitarsus of the middle legs. I couldn't clearly discern such pegs under the microscope, though perhaps some will see evidence of them in the full-size version of the 3rd image in the series here. Under the scope, the terminalia agreed roughly with that of Fig. 111.30 of the male
Icosta americana on pg. 1278 of the MND
(1)...but I'm not really sure whether this is a male or female.