Williamson County, in comparison with its neighbor Travis County, has been relatively unexplored, unreported, and undescribed in terms of native flora. Thanks to members of the Native Plant Society of Texas, including both professional and amateur botanists, and the collaboration of both county government and other entities, progress has been made in recent years in identifying and reporting the native flora of Texas in this county. The story of the chapter’s directed efforts will have to wait for a different day, however. This story is about the serendipitous finding of Phemeranthus calycinus while trying to get photographs of Lace Cactus virtually in my own backyard.
Our story begins in the Spring of 2016 as wildflowers across Texas burst into bloom. I had previously found several colonies of Lace Cactus (Echinocereus reichenbachii) in the greenbelts near where I live, flourishing in the thin soil on top of solid limestone that characterizes the habitat available to plants in this transitional area between the Edwards Plateau and the Blackland Prairies. As luck would have it, in addition to the Lace Cactus, which seemed to be having a somewhat less than spectacular bloom season, a small pink flower caught my eye in the midst of a sea of yellow Four-nerve daisy (Tetraneuris scaposa) and Texas prickly pear cactus (Opuntia engelmannia var. lindheimeri) blossoms. At first, I thought it might be Prairie Rose-gentian (Sabatia campestris) which I had seen earlier in April at a different location, but it clearly was not the same plant. A cursory search of the photos in my illustrated guides did not reveal an answer, so I went to plan B – digital photos were emailed to our resident plant identification experts, including amateur and professional (retired) botanists in hopes that they would recognize it. My initial photos were not well enough focused or detailed enough to reach a definitive identification, so I continued to visit the location.
Additional visits and photos shared later, the following information had been reported to my expert resources:
- Leaves were thin, smooth, glabrous, fleshy and located at the base of the plant
- Flowers were located on a thin, bare stem that extended above the basal leaves for about 6 to 8 inches
- The stem branched out towards the end so there were several flowers on each plant, though they seemed to be in different phases of maturity.
- Flowers had 5 petals, were pink (had to check the original digital photos to make sure that no additional saturation had been done to the pictures – some contrast or de-hazing might have been done, but no, the hot pink petals were pretty faithful to nature.
- Each flower had one long stigma and many stamens.
In spite of this data and the suggestion that the plant in question might be in the Portulacaceae, the closest I was able to get to an identification was the possibility that it was either Phemeranthus parviflorus, or Phemeranthus teretifolius. The latter does bear some resemblance but has not been reported in Texas. However, with the meaning of parviflorus defined as “small flowers”, this was not likely to be correct. Finally, Dr. Art Gibson, a retired botanist living in Georgetown and a member of the Williamson County Chapter, identified the plant as Phemeranthus calycinus. Dr. Gibson has written the species description of this plant, as well as many others in the last few years which were previously unreported for Williamson County. The descriptions are being published online through the University of Texas/Plant Research Center website (as resources permit) in detailed, professional descriptions of the species.
Phemeranthus calycinus (common name Rock Pink) was first described by George Engelmann based on materials collected by F.A. Wislizenus during a tour of North Mexico (where he was held prisoner for several months) in 1846 and 1847, published in 1848. Previously named Claytonia calycina and Talinum calycinum, it is only recently that the genus Phemeranthus has come into accepted use. Constantine Samuel Rafinesque transferred Talinum teretifolius to the separate Genus Phemeranthus (from the Greek ephemeros “lasting for a day” or “short-lived” and anthus “flower”) in 1814, but most authors continued to use the earlier designations until after 2000 and 2001, when molecular studies were conducted which clearly established the close relations of the species. Many of the popular field guides and references used in Central Texas (e.g., those authored by Enquist, Correll & Johnston, or Shinner & Mahler) were published before this time and thus refer to Talinum as the genus.
According to Flora of North America, P. calycinus blooms from May through October, which is consistent with my own observations. The soil in which it was found was definitely rocky, and part of an area with more limestone outcrop than soil. The presence of caves beneath the rocky surface and endangered species within those caves certainly contributed to the preservation of the habitat within the greenbelt. The lack of trained eyes and the ephemeral nature of the flowers – lasting for only a day, or only an afternoon, certainly contributed to the delay in finding the species within this county. My own lack of expertise and knowledge in the field of botany, fortunately, did not prevent a successful identification in the long run. Even if you do not know a professional botanist, you can always post photos of an unidentified plant to the Texas Flora Facebook group and get the assistance of several professional botanists, as was done with the possible Portulaca pilosa shown in the slide show above.
The moral of the story, if it has one, is that even an amateur can find something “new” if one has the sense to persist, to seek assistance from the experts, to look in places of no use to the general public for recreation, and above all, to keep your eyes wide open or you just might miss the afternoon when the plant comes into bloom. Of course, it helps to have some places set aside for preservation as natural areas, to be in a county with relatively low population density, relatively low agricultural development, and low urban development. Who knows? You or I might never discover a new species, but we might find a plant that has previously been unobserved or unreported in our county.