Flora of New Zealand Series

P. scottii Elix & A.W.Archer, in J.A. Elix, W.M. Malcolm & A.W. Archer, Mycotaxon 53: 278 (1995).

Holotype: New Zealand. Canterbury, Lake Tekapo near Cass River, 2400 ft. [730 m], in short tussock grassland, 29.viii.1958, D. Scott s.n. – OTA 257.

Description : Thallus chalky white, surface smooth and dull, without isidia or soredia. Apothecia verruciform, numerous, conspicuous, concolorous with thallus, often confluent and covering thallus, individual verrucae 0.4–0.6 mm diam., ostioles conspicuous, black, sometimes sunken, 1 per verruca. Ascospores 8 per ascus, ellipsoidal, smooth, mainly uniseriate, 45–55 × 25–30 μm.

Chemistry : K−, C−, KC−, PD−; containing 4,5-dichlorolichexanthone and 2- O -methylperlatolic acid (Elix et al. 1995b: 278).

S: Canterbury (Cass River, Lake Tekapo). On plant debris and dead moss.

Endemic

Illustration : Elix et al. (1995b: 277, fig. 5).

Pertusaria scottii is characterised by: the muscicolous/corrticolous habit; verrucae with conspicuous black ostioles; 8 ascospores per ascus; and the presence of 4,5-dichlorolichexanthone and 2- O -methylperlatolic acid. The smaller ascospores and the absence of stictic acid distinguish P. scottii from the superficially similar muscicolous species P. tyloplaca.