Small Butterwort (Pinguicula pumila) in its natural habitat

Abstract

Two wild populations of Small Butterwort (Pinguicula pumila, Lentibulariaceae) were studied during its 2019/2020 late autumn–spring flowering season in Palm Beach County, Florida. The rare yellow-flowered form known primarily from Southwest Florida turned up in East Florida. Except possibly for 19th century literature we were unable to examine, stigmatic curling in response to touch is first reported for Pinguicula. Diverse Dipteran and Hymenopteran floral visitors were observed. Previous indications that spontaneous self-pollination is rare to none in this and related species, especially with reference to cultivated plants, were consistent with our results using insect exclosures on wild plants, whereas open-pollinated flowers made fruits and seeds abundantly. In our area the known populations are all spotty and small, in wet-then-dry disturbed habitats.