New insights into the natural history of  the woolly devil Ovicula biradiata (Helenieae):
chromosome number, UV reflectance, and a range extension

Isaac Lichter Mark

Dept. of Botany, Institute for Biodiversity Science & Sustainability, California Academy of Sciences, 55 Music Concourse Dr., San Francisco, CA 94118, USA

https://orcid.org/0000-0003-3575-6003

A. Michael Powell

Dept. of Natural Sciences, Sul Ross State University, East Highway 90, Alpine, TX 79832, USA

Kelsey A. Wogan

Dept. of Natural Sciences, Sul Ross State University, East Highway 90, Alpine, TX 79832, USA

DOI: http://dx.doi.org/10.53875/capitulum.04.1.01

ABSTRACT:  The rare desert annual Ovicula biradiata was discovered in March of 2024 and recently described as a new genus and species. Few details about this enigmatic new composite are yet known, including its geographic distribution, reproductive biology, or chromosome number. Here we report a new record for the woolly devil and biological observations from four individual plants that were grown from seed. The cultivated plants of O. biradiata, from seedling to maturity, were not as densely white-woolly as plants in the field. The potted plants grew rapidly, producing solitary capitula at branch tips. The first flower parts to emerge from phyllaries were the strap-like limbs of 2–3 ray floret corollas, soon followed by the disc floret corollas already with yellow, pollen-laden anthers.  A chromosome number of 2n=32 was obtained for the species based on meiotic counts. We report preliminary evidence for reproductive self-incompatibility in the woolly devil, and the tendency for ray florets to fluoresce under ultraviolet light, suggesting they contrast with the overall cryptic appearance of the plants and aid in pollinator attraction. Finally, we report a new photographic observation recently uploaded to iNaturalist that, if substantiated, extends the range of the woolly devil eastward by over 130 km.

Keywords: ex-situ conservation, iNaturalist, pollination, self-incompatibility, Trans-Pecos Texas, UV reflectance.