One of VERY few flowering plants that Greg and I noted on our entire 3000-mile trip through TX-OK-NM. This "verbena" was blooming on the roadside adjacent to fallow cropland on FM 2185 outside of Van Horn, TX.

The distinguishing characters here are the large flowers, the low, mat-like growth form, and--if you look carefully--the involute (rolled in) leave margins.

I had more trouble tracking down the current scientific name of this plant than I did in identifying it in the first place. In the Manual, this keys out to "Verbena ciliata var. pubera". Subsequently, this genus was split into Verbena and Glandularia, of which the latter includes this plant. But the maps on the BONAP site have only Glandularia pubera and the similar G. wrightii for Culberson County. My final go-to source (itis.gov) lists the latest valid name for this plant as G. bipinnatifida var. ciliata. Whew! It is known as Davis Mountain mock vervain, an English name which I will add to the iNat database.