Flora of New Zealand Series

H. scalaris (Ach. ex Liljeblad) M. Choisy, Bull. mens. Soc. linn. Lyon 22: 103 (1953).

Lichen scalaris Ach. ex Liljeblad, Utkast. sv. fl.: 422 (1792).

Thallus squamulose, squamules 1-1.5 mm diam., greenish-white to pale brown, shell-like, crowded-congested, imbricate, margins entire, upturned, closely attached to substrate at centre, margins free and ± subascendent, sorediate below at margins. Soredia white or grey-white, granular. Apothecia (not seen in New Zealand material) 0.5-0.7 mm wide, black. Hymenium c. 50 µm tall, amyloid. Paraphyses thin, septate, apices not noticeably thickened. Ascospores ellipsoid, 9-12 × 2.5-4 µm. Chemistry: Medulla and cortex K-, C+ red, KC-, Pd-. Lecanoric acid.

S: Nelson (Lake Rotoroa). Rare on decorticated and charred wood (Dacrycarpus).

Cosmopolitan