Synonyms: Crocynia grevilleana B. de Lesd.; Lepraria lesdainii (Hue) R.C. Harris
Distribution: N - VG (Baruffo & al. 2006), Frl (Baruffo & al. 2006), Ven (Thor & Nascimbene 2007), Lomb (Baruffo & al. 2006), Emil (Baruffo & al. 2006, Fariselli & al. 2020), Lig (GE 151). C - Tosc (Baruffo & al. 2006), Sar (Kümmerling & Leuckert 1993, Baruffo & al. 2006). S - Si (Kümmerling & Leuckert 1993, Grillo 1998, Grillo & al. 2001, Grillo & Caniglia 2004, Baruffo & al. 2006).
Description: Thallus leprose, byssaceous, cottony, forming 1-3 mm thick, to several cm wide patches (sometimes 1 dm or more), dull, pale lime-green, entirely composed of very lax mass of thin-walled, hyaline, anastomosing, 2-3.5 µm thick hyphae with numerous septa, without soredia-like granules. The hyphae are mainly erect, and bear laterally, in their distal parts, shrub-like clusters of 1-3 algal cells which are up to 15(-20) µm wide in a form resembling a bunch of grape. Medulla not evident. Photobiont chlorococcoid, the algal cells mostly spherical, single or forming short filaments no more than 3 cells long, 2.5-6(-10) µm thick, each cell with a nucleus and a parietal cup-shaped chloroplast with lobes, filling more than half of the cell periphery. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: lesdainin, and a range of unidentified terpenoids (mostly in traces).
Note: on limestone, calcareous sandstone, epilithic mosses and soil, sometimes on walls, especially in fissures, in shaded sites protected from rain, certainly much more common throughout Italy, below the subalpine belt. According to Baruffo & al. (2006) this is the most shade-loving among all leprarioid species.
Growth form: Leprose
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)