Flora of New Zealand Series

Description : Thallus corticolous and saxicolous, yellow-green to pale-green, shrubby to subpendulous, 1–3.5 cm long, branching irregular, dense. Holdfast delimited. Branches 0.2–2 mm wide, flat to subterete, often palmate at base to 6 mm broad, apically producing numerous fine, fibrillar branches. Surface smooth, sometimes wrinkled, shining or matt. Soralia occur in eroded patches at apices of lobes and where branches have split and flattened out. Apothecia rare, disc 2 mm diam., concave to plane, margins entire. Ascospores ellipsoidal, straight or curved, 10–12 × 4–4.5 μm.

Chemistry : Medulla K−; containing usnic and divaricatic acids.

N: South Auckland (Waikato, Pureora) to Wellington (Kapiti I.). S: Nelson to Southland [map in Bannister et al. (2004: 131, fig. 7)]. E of the Main Divide and more frequent in Otago and Southland where it is common [J. Bannister, pers. comm.]. Widespread, but sparse to rare in any site – often small and easily overlooked (Bannister 1998; Bannister et al. 2003). On trees and shrubs (Acer pseudoplatanus, Aristotelia serrata, Coprosma, Crataegus, Dacrycarpus dacrydioides, Dacrydium cupressinum, Discaria toumatou, Elaeocarpus, Fuchsia excorticata, Kunzea ericoides, Nothofagus, Olearia virgata, Pennantia, Podocarpus totara, Populus, Pseudopanax, Quercus, Prumnopitys taxifolia, Sorbus aucuparia), fence posts and occasionally on rocks, s.l. to 400 m. Known also from South Africa, Australia and South America (Stevens 1987; McCarthy 2003c, 2006).

Austral

Illustrations : Stevens (1987: 171, pl. 9, figs 5, 6); Blanchon et al. (1996a: 78, fig. 7G; 85, fig. 9H).

Ramalina unilateralis is characterised by: the corticolous/lignicolous (occasionally saxicolous) habit; very variable small thalli, often densely branched at apices; and the cortex splitting laminally (but not at margins) to release soredia.