in Wirth, Flechtenflora, 2 Aufl.: 634, 1995. Basionym: Thelidium acroglyptum Norman in Fries - Bot. Not.: 154, 1868 (1867).
Synonyms: Lauderlindsaya acroglypta (Norman) R. Sant.
Description: Thallus crustose (sometimes indistinctly subsquamulose when young), episubstratic, grey-green, diffuse, consisting of granular, goniocyst-like units and scattered, diffuse 60-250 μm thick soredia. Perithecia black, 0.2-0.4 mm across, semi-immersed in thallus. Exciple reddish brown but irregularly pigmented; involucrellum absent; hamathecium of periphyses, interascal filaments absent; hymenial gel I+ red (I+ yellowish or blue at low concentrations of I), K/I+ blue. Asci 8-spored, clavate, short-stalked, with delicate walls, K/I-. Ascospores (3-)5-7-septate, hyaline, ellipsoid-fusiform, (23-5)27-37(-43) x (5-)6-7.5(-8.5) μm. Photobiont chlorococcoid. Spot tests: thallus K-, KC-, C-, P-, UV+ orange-pink after heating. Chemistry: two unidentified terpenoids.
Note: on mossy siliceous rocks. For further details see Orange (2022). The species is known from Austria, and should be looked for also in Italy.
Growth form: Crustose
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)