Visiting flower heads of the composite shrub Lepidospartum squamatum growing near a dry creek bed in an arid juniper/pinyon pine woodland on north side of the Transverse Range.

This has the appearance of a tiphiid and keyed to that family using Goulet & Huber(1). I'm not certain, but my best attempt to count flagellomeres (10) and visible tergites (6) would indicate a female here (cf. pg. 178 of (1)).

As for the genus, the wing venation exhibits the distinctive character of Paratiphia...that is, there's a long spur vein which almost separates the 1st submarginal cell (cf. description on pg. 131 of Pate (1947) and pg. 234 of Allen (1966), and the 4th image in this series).

As far as species goes, I tried to work through Allen (1968) but the key there is for males only. Nevertheless, my best shot is P. robusta. The description of that species fits well: the long, dense hair of the lower frons; the long tibial spurs on the mid-tibia (see 4th image); the thin transverse carina near the base of tergite 1 (barely visible in image above); and the relatively large size...females of robusta and the largest in the genus. Also, the details of the short apical bands of hairs on the terga fit P. robusta well...but this and most the other characters (except for large size for females) is apparently shared by various other species as well. The range map for robusta on pg. 69 of Allen (1968) in one of the few that clearly covers the locale here (the other being nevadensis, and less so cincta).