Moved from Mydas Flies.

This is in subfamily Leptomydinae, and the proboscis, which can barely be discerned (in line-of-sight between the antennae), is clearly quite long...which indicates Pseudonomoneura.

Due to the somewhat rufous legs, and the reddish antennal clubs, this pair does not key to P. californica...which has black legs and black antennal clubs in both sexes according to the references Hardy(1950) and Fitzgerald & Kondratieff(1995).

In fact, due to the rufous legs, this mating pair keys to P. hirta in Hardy(1950), whereas using the key in Fitzgerald & Kondratieff(1995) it goes to either P. hirta or P. micheneri, based on the reddish (vs. black) antennal clubs...with the white (vs. yellow or grey) hairs of the abdomen suggesting P. micheneri (vs. hirta), though in their treatment a conclusive ID would require assessment of subtleties in the shape of parts of the terminalia not visible here.

Note that P. hirta is an extremely variable species, according to the discussions in both Hardy and Fitzgerald & Kondratieff. But the both references indicate that in that species the male's abdominal dorsum is almost always entirely black in base color, though it may be covered with dense bands of yellow or grey hairs.

All the above suggested giving further consideration for P. micheneri, even though Hardy indicated in has "legs black and conspicuously white pilose"...which doesn't seem to fit well here.

However, on scanning James's original 1936 description of (Psuedo)nomoneura micheneri, I noticed he described the males as having "legs black, with knees and tarsi brownish" (emphasis mine); and the females as having "tibiae brownish". Noting this apparent contradiction to the "legs black" condition in Hardy's key...and given that Hardy's discussion of micheneri states James' description is "adequate" (except for a few points which don't involve leg color)...I was emboldened to carefully go through James' description of P. micheneri point-by-point, and compare it to the mating pair here.

Doing so, I found excellent agreement between James' description and both the male and female here in nearly all the (many) visible characters. The only discrepancy is the brownish (rather than "black") hind tibia of the male...which, on balance, doesn't seem disqualifying. Although, ideally, it would be nice to be able to verify the correct shape of the terminalia, I think the otherwise excellent agreement of James' description here is sufficient to tentatively move this post to P. micheneri.

Nice find, Steven :-)

Moved from ID Request.