Flora of New Zealand Series

Description : Thallus immersed, inconspicuous or a thin, greyish and shining film. Prothallus indistinct. Soredia bright orange-yellow, crowded, plane to convex, rounded, discrete, eroding to superficial; soredia minutely granular. Apothecia rare, to 1 mm diam., scattered, somewhat elevated, rounded, concave at first becoming plane, thalline margin sorediate, disc orange. Paraphyses 2 μm thick, apices slightly thickened (to 3 μm). Ascospores (10–)13–20 × 7–10 μm, ellipsoidal, septum 3–5 μm thick.

Chemistry : Soredia and apothecia K+ violet-red; contaning emodin, parietin and fragilin (Santesson 1970: 2152).

S: Canterbury (Lake Lyndon). On twigs and branches of Dracophyllum acerosum. Still very poorly collected in New Zealand. Known also from E Scotland, Angelsey, Bardsey and the Isles of Scilly (Laundon 1992; Fletcher 2001a), Scandinavia where it is rare and endangered (Thor 1996; Thor & Arvidsson 1999), Europe where it is also rare and probably extinct over much of its former range (Nimis & Poelt 1987), the Azores, Ukraine, the Himalaya, North America (Arvidsson 1990; Nimis 1993; Esslinger & Egan 1995; Kondratyuk et al. 1996b, 1998; Ihlen 1997b: 33–34; Scholz 2000; Diederich & Sérusiaux 2000; Hafellner & Türk 2001; Llimona & Hladun 2001; Nimis & Martellos 2003) and Tasmania (Kantvilas 1994b; McCarthy 2003c, 2006).

Bipolar

Illustrations : Foucard (1990: pl. 69); Thor & Arvidsson (1999: 241).

Caloplaca chrysophthalma is characterised by: the corticolous habit; the orange-yellow, delimited soralia and the immersed to thin, shining greyish thallus. It may be confused with forms of C. citrina but in this species the soralia are not delimited.