Uvulifera Molinari.

The genus Uvulifera (Fig. 17), originally described as Coccobotrys by Chodat (1913), possesses a morphology very similar to that of Apatococcus . The thallus consists of globular to slightly elongated cells, often forming sarcinoid three-dimensional colonies, and, occasionally short, branched, easily disintegrable filaments. The chloroplast is simple, parietal without a pyrenoid. Reproduction occurs by zoospores or aplanospores (Vischer 1960). The two currently accepted species ( U. mucosa, U. verrucariae; Guiry & Guiry 2022) are closely related to Xerochlorella (Mikhailyuk et al. 2020) . The type species U. verrucariae was identified as a photobiont of Verrucaria nigrescens based on light microscopy observations (Chodat 1913). Free-living and lichenized cells were observed in limestone cavities (Roldán et al. 2004). Moreover, it occurs free-living on buildings (Barberousse et al. 2006) and in soil (Flechtner et al. 2008; Stewart et al. 2021).