One of Texas' Rarest Plants - Paronychia congesta

I recently got a chance to visit one of Texas's rarest plants, which not surprisingly gross on a unique soil formation that appears to be pure caliche. This plant has only been collected from two different sites and I believe it has only been collected twice. It recently received endangered species status.

The genus Paronychia has quite a few species, most of them occurring on dry sites or in dry regions. Paronychia jamesii is a more common species throughout much of Texas, built as it is to tolerate heat and drought. Paronychia congesta, however, seems uniquely adapted to tolerate the brutal heat of South Texas. All species in this genus are generally smaller plants and tend to be somewhat matted. P. congesta has very abbreviated leaves with short-to-nonexistent internodes, the branches and leaves covered in hairs and scales which no doubt greatly benefit it and prevent it from transpiring moisture while at the same time reflecting heat and light.

It was co-occurring with Euploca torreyi, Liatris punctata var mexicana, Stenaria nigricans, Calliandra conferta and Nahuatlea hypoleuca on these harsh caliche exposures. Caliche is basically a natural cement formed by the dissolution and subsequent precipitation of the minerals weathered out of calcareous country rock.