Wing of female of Mythicomyia rileyi from Fig. 45.27 on pg. 594 of McAlpine (1981) Key to Families - Adults,
Manual of Nearctic Diptera
, Ottawa, p.89-124, (1981)
[1].

Description of the abbreviations contributed by Aaron Schusteff:

Veins ("traditional names" used in older literature appear in parentheses):

• {R1...[not labelled on diagram] = 1st branch of the radial vein ("first longitudinal vein")...this vein bounds cell r1 "from above" [i.e. anteriorad]}
• R2+3 = branch formed from fusion of the 2nd and 3rd branches of the radial vein ("second longitudinal vein"). In Mythicomyia this vein is unusually short and bends anteriad to join R1 near where it meets the wing margin.
• R4+5 = branch formed from fusion of the 4th and 5th branches of the radial vein ("third longitudinal vein")
• bm-cu = basal medial-cubital crossvein
• dm-cu = discal medial-cubital crossvein

Cells:

• br = basal radial cell (or "1st basal cell")
• bm = basal medial cell (or "2nd basal cell")
• dm = discal medial cell (or simply "discal cell")
• r1 = cell posterad to vein R1 ("marginal cell"...it is relatively short in Mythicomyia)