Flora of New Zealand Series

Holotype: New Zealand. Northland, Anawhata Bay, on rotten rocks on coastal cliffs, L.M. Cranwell s.n. – W. Isotype – CHR.

Description : Thallus irregularly spreading, thin, 0.2–0.3 mm thick, tartareous, dirty white to brownish grey, minutely areolate, with a pale, marginal prothallus. Areolae angular, 0.3–0.7 mm diam. Apothecia lecideine to biatorine, black to grey-black, with a persistent, thin, black margin, rounded, to 1 mm diam. Epithecium blackish. Hymenium colourless, 60–90 μm tall. Hypothecium colourless, Asci oblong-clavate. Ascospores ellipsoidal, 9–10 × 5.5–6 μm.

Chemistry : not tested.

Endemic

Lecidea senescens is characterised by: the saxicolous habit (coastal rocks); the creamish to grey-brown, areolate thallus; convex, biatorine, black to grey-black apothecia; a blackish epithecium; a colourless hypothecium; and ellipsoidal ascospores, 9–10 × 5.5–6 μm. As indicated above, this species is not correctly accommodated in Lecidea s. str.