Various Identification Issues with Pyrgotidae on BG

I've become very interested in Pyrgotidae after photographing Sphecomyiella nelsoni and Boreothrinax maculipennis at the recent BugGuide gathering south of Tucson at the end of July. Since then I've been studying as much of the literature as I can find on the family, and working on IDing and sorting some of the BG pyrgotid posts. A forum seemed the best venue for addressing the following items:

1) Since 2006, a number of BG posts have been placed under the name "Pyrgota" maculipennis. But it appears very likely that name was incorrect, and that Boreothrinax maculipennis was the valid name. For details on how and why this occurred, see the remarks and comments accompanying the post below:

       

I'm currently trying to get confirmation and feedback from experts and BG editors to resolve this issue, so we can get the correct genus name for all the BG posts placed as this taxon.

2) The three species Specomyiella valida, S. nelsoni (see below), and Boreothrinax (=Pyrgota) maculipennis are very similar looking, and mistaking one for the other has been a common occurrence on BG.
See the comments appearing with the posts below for a discussion of how to distinguish these taxa:

       

3) In 1993 a new species, S. nelsoni, was described by Kondratieff & Fitzgerald within the previously monotypic genus Sphecomyiella. That species is virtually identical to S. valida in external appearance, but differs in subtleties of the terminalia. In studying Sphecomyiella material from many collections, it was found that all those specimens from southern Arizona conformed to S. nelsoni, while all those from the remainder of the range (from Colorado to the eastern US) conformed to S. valida. As of this writing, the one BG post from southern AZ in which the terminalia are visible also conforms to this pattern. See the posts below:

       

While it may be appropriate for a museum to insist on checking terminalia before filing actual specimens under one name or the other, for images with no available info on terminalia I have used a southern Arizona locality to place Sphecomyiella posts under S. nelsoni. In the "photo-centric" context of BugGuide, this seems an appropriate alternative to placing all Sphecomyiella without terminalia info to genus only. (If this practice is thought to be inappropriate here, please let me know.)