Caloplaca chrysodeta
≡Placodium chrysodetum Vain. ex Räsänen, Annls Acad. Sci. fenn. A 34 (4): 113 (1931).
≡Leproplaca chrysodeta (Vain. ex Räsänen) J.R.Laundon, Lichenologist 6 (1): 103 (1974).
Description : Flora (1985: 247 – as Leproplaca chrysodeta).
Chemistry : Thallus K+ violet-red, C−; containing parietin.
S: Canterbury (Weka Pass), Otago (Rees Valley), Southland (lower slopes of Mt Luxmore). On ±shaded, vertical or overhanging limestone or basic rocks; still very poorly known here. Known also from Great Britain, Scandinavia (where it is rare and endangered), northern central and southern Europe, Macaronesia, North and South America (Poelt 1969; Laundon 1974, 1992; Nimis 1993; Santesson 1993; Wirth 1980, 1995b; Arup & Ekman 1997; Thor & Arvidsson 1999; Diederich & Sérusiaux 2000; Boqueras 2000; Wetmore 2001; Nimis & Martellos 2003; Santesson et al. 2004).
Bipolar
Illustrations : Dobson (1979: 141; 2000: 215 – as Leproplaca chrysodeta); Arup & Ekman (1997: 169, fig. 68C); Thor & Arvidsson (1999: 241); Wetmore (2001: 5, fig. 5).
Caloplaca chrysodeta is distinguished from other sterile lichens by its greenish yellow to brownish yellow or brownish orange thallus composed entirely of pulverulent spherical granules reacting K+ violet red. Laundon (1974) re-established use of the genus Leproplaca for the two sorediate taxa C. chrysodeta and C. xantholyta, but this position is no longer tenable as the taxa are merely very reduced forms of Caloplaca (Poelt 1987; Kärnefelt 1989; Nimis 1998; Wetmore 2001). C. chrysodeta is distinguished from C. xantholyta in its dull colour and lack of marginal lobes; and from C. citrina, which grows in more highly illuminated habitats (also often on concrete) and which has soredia that are vivid to deep-yellow or rarely orange, and which also occasionally has thalline granules present that coalesce into soredia, a feature unknown in C. chrysodeta.
