Collema crispum
≡Lichen crispus Huds., Fl. angl.: 447 (1762).
Description : Flora (1985: 134).
N: Known from one collection from stone walls in the Wellington Botanic Garden. Known also from Great Britain, Europe, Scandinavia, and North America (Degelius 1974; Nimis 1993; Santesson 1993; Esslinger & Egan 1995; Nimis & Martellos 2003; Santesson et al. 2004; Schultz et al. 2004).
Cosmopolitan
Illustrations : Degelius (1954: 39, fig. 4B; 45, fig. 5G; 79, fig. 10D; 285, fig. 43; pl. III B); Wirth (1987: 169); Goward et al. (1994b: 43, fig. 5B); Dobson (1992: 128; 2000: 140 ; 2005: 151); Sérusiaux et al. (2004: 70).
Collema crispum is characterised by: the saxicolous habit (calcareous walls or old mortar); the numerous, ear-like, often overlapping lobes with flattened, squamiform isidia that are often so densely developed they obscure the thallus; infrequent, sessile apothecia, with a thin, granular to lobulate thalline margin; and 3-septate to submuriform ascospores, (17–)26–34(–47) × (8.5–)13–15(–18) μm.