Polyblastia melaspora
≡Verrucaria melaspora Taylor, Lond. J. Bot. 6: 153 (1847).
Description : Thallus moderately thick, off-white to pale greenish grey. Perithecia semi-immersed to almost superficial, with a thick, black, 0.4–1 mm diam. involucrellum, a plane to subconcave apex, a medium-brown exciple, and 8-spored asci. Ascospores medium- to dark-brown, ellipsoidal to subglobose, muriform, (27–)33(–40) × (18–)21(–27) μm.
Chemistry : TLC−, all reactions negative.
S: Southland (Brod Bay Lake Te Anau). On boulders and bedrock sandstone beneath forest edge on lake shore. First collected in New Zealand by Dr Peter Johnson in March 1993 (McCarthy & Johnson 1995: 499). In The Northern Hemisphere it has an arctic-alpine distribution being known from the British Isles, Europe, and Scandinavia (Swinscow 1971; Hawksworth 1978; Purvis & James 1992d; Nimis 1993; Santesson 1993; Nimis & Martellos 2003; Santesson et al. 2004).
Bipolar
Illustration : Swinscow (1971: 111, fig. 18 – as Polyblastia scotinospora).
Polyblastia melaspora is characterised by: the saxicolous habit; the prominent, conspicuous perithecia contrasting with the pale thallus; and the brown to dark-brown ascospores, 27–40 × 18–27 μm.
