Pyrenopsis (Nyl.) Nyl.
Type : Pyrenopsis fuscatula Nyl., typ. cons.
Description : Thallus crustose, effuse, granular-areolate or minutely squamulose; blackish or tinged reddish (especially when moist); ±gelatinous when moist; cortex not differentiated, ±paraplectenchymatous throughout. Photobiont cyanobacterial Chroococcidiopsis or Gloeocapsa, cells or cell-clusters near the upper surface with reddish brown, K± purplish gelatinous sheaths. Ascomata apothecia, perithecia-like; disc pore-like to urceolate, orange-brown to blackish; thalline exciple prominent, proper exciple very thin, often inconspicuous. Hymenium colourless or pale-brownish above, I+ blue-green or reddish brown. Hypothecium colourless or pale brownish. Hamathecium of simple to branched paraphyses that are often ±moniliform at apices. Asci clavate, 8- to multi-spored; apical dome I+ blue. Ascospores simple, ellipsoidal to globose, colourless, without a perispore. Conidiomata pycnidia, immersed; wall colourless. Conidiogenous cells in chains. Conidia shortly ellipsoidal to bacillar, simple, colourless.
Pyrenopsis is included in the family Lichinaceae (Henssen 1963d, 1980; Henssen et al. 1987; Jørgensen & Henssen 1990; Henssen & Jørgensen 1994; Eriksson et al 2004; Pennycook & Galloway 2004). Some 40 species are recognised worldwide, occurring on damp rocks or rarely on soil in humid habitats in cool temperate to polar regions in both Northern and Southern Hemispheres (Jørgensen & Henssen 1990; Coppins et al. 1992b). Nomenclatural problems surrounding Pyrenopsis and related genera are detailed and resolved by Jørgensen & Henssen (1990) who elaborate a proposal to conserve the genus with a conserved type. One species is known from New Zealand.
