Caloplaca marina (images of British lichens)

Thallus a discontinuous areolate crust, often (but not always) slightly lobed at the margins, orange-yellow to strongly orange; apothecia deeper orange. Common around the coast on hard, maritime rocks, characteristically a component the yellow Xanthoria/Caloplaca zone above the black Verrucaria maura zone on rocky shores.

Refs: Arup (1997), Lichenologist 29: 503-512 (photo and comparison with C. maritima); Smith et al. (2009), 266; Purvis et al. (1992), 154-5 (excluding last three sentences, which clearly refer to C. maritima as now understood); Dobson (2005), 105 (photo); Dobson (2011), 114 (photo); Allen (2007), 13 (photo, habitat); Dalby & Dalby (2005), 23 (photo); Jahns (1983), 246-247 (photo); van Herk & Aptroot (2004), 102-103 (photo); Moberg & Holmåson (1984), 187 (photo); Thomson (1997), 165; Lichen Atlas of the British Isles 6: 267 (2001).

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Images of British Lichens