Moved from Paracosmus.

For the subfamily Tomomyzinae:

    1) occiput roundly inflated ("swollen"-looking), and medially cleft & bilobed above; body mostly bare, with no bristles and only very fine pubescense;

For the genus Paracosmus:

    2) two submarginal cells; with vein R2 sharply bent forward at apex;

For species rubicundus:

    3) antenna with basal segment yellow, remainder of segments black;
    4) vertex with large black spot;
    5) wings "water-clear" hyaline with yellowish veins;
    6) most conspicuous character among congeners...the only Paracosmus species with abdomen not mostly black!

Looks like this one was perched on a Cryptantha plant (perhaps C. angustifolia).