Flora of New Zealand Series

Holotype: New Zealand. Otago, Akatore River mouth, on shrubs, i.1963, W. Martin 5642 – CHR 480045. Isotypes – BM, WELT.

Description : Thallus corticolous, yellow-green, rigid, erect, 1–3 cm tall, branching dense to moderate, dichotomous. Holdfast delimited or diffuse in dense colonies. Branches narrow, to 2 mm wide, inflated, perforate, apices attenuate. Surface smooth, matt, pseudocyphellae rare to absent; without soralia. Apothecia common, terminal or subterminal, geniculate, subtending a spur; disc to 3 mm diam., concave at first then plane, margins entire. Ascospores ellipsoidal, straight or curved, 11.5–17(–20) × 4–6 μm.

Chemistry : Medulla K+ pink; containing divaricatic acid, sekikaic acid, salazinic acid and usnic acid.

S: Otago (Carey's Creek N of Dunedin, Taieri Mouth, Akatore, Wangaloa Hill, Catlins), Southland (Tiwai Point, Clifden) [map in Bannister et al. (2004: 143, fig. 9)]. On bark and twigs of both native and introduced trees and shrubs: Carmichaelia, Coprosma, Corokia, Cupressus macrocarpa, Cytisus scoparius, Kunzea ericoides, Melicope simplex, Metrosideros umbellata, Myrsine divaricata, Olearia bullata, Podocarpus totara, Salix, Sorbus aucuparia, Weinmannia, at forest margins or near river banks. s.l. to 100 m.

Endemic

Illustration : Blanchon et al. (1996a: 78, fig. 7F).

Ramalina riparia is characterised by: the corticolous habit; narrow, fully inflated branches with attenuate apices; perforations narrow and slit-like; and salazinic acid in the medulla.