Thelidium calcareum
≡Verrucaria calcarea C.Knight, Trans. N. Z. Inst. 15: 356 (1883).
=Verrucaria calcicola Nyl., Lich. Nov. Zel.: 127 (1888).
Holotype: New Zealand. Sine loco. Charles Knight – WELT. Isotypes – BM, H-NYL 2107 (see below), H.-NYL 2092.
Verrucaria calcicola. Type: "Nova Zelandia" [New Zealand]. Sine loco (probably Wellington), 1882, [Charles] Knight – H-NYL 2107 – holotype [labelled by Knight "V. calcarea Knight", and annotated with Nylander's drawing of 1-septate spores "0.014–18, 0.007–8" (Dr Orvo Vitikainen, pers. comm.)].
Description : Flora (1985: 570).
N: South Auckland (Pio Pio) to Wellington. S: Canterbury (Weka Pass, Castle Hill, Mt Somers), Otago (Maheno, Oamaru), Southland (Castle Rock, Clifden). On limestone rocks, often giving a rather greyish colour to stone – widespread.
Endemic
Illustration : Knight (1883: pl. XXXVI, fig. 11 – as Verrucaria calcarea).
Thelidium calcareum is characterised by: the saxicolous habit (basicolous rocks); the olivaceous to blackish brown, rather effuse or abraded thallus; minute, black perithecia; and 1-septate ascospores, 14–18 × 7–9 μm.