Flora of New Zealand Series

≡Parmelia dielsii Hillmann, Feddes Repert. 49: 38 (1940).

Type : New Zealand. Canterbury, Broken River, on Nothofagus solandri var. cliffortioides, L. Diels –?B [not seen – possibly destroyed in World War II].

Description : Flora (1985: 281).

Chemistry : Medulla K+ yellow, C−, KC−, Pd+ orange; containing atranorin (cortex), psoromic, conpsoromic and echinocarpic acids.

N: S of lat. 38ºS (Lake Waikaremoana) S: Nelson–Marborough (Omaka Valley), Canterbury (Arthur's Pass to Lake Ohau), Otago (Rees Valley, Lake Howden, Maungatua) to Fiordland. St: (Mt Anglem, Glory Cove). On beech bark in beech forest, and on mossy rocks and subalpine scrub, s.l. to 1000 m.

Endemic

Illustrations : Martin & Child (1972: 80, pl.13); Malcolm & Galloway (1997: 71, 101, 175); Australasian Lichenology 46 (2000: back cover); Malcolm & Malcolm (2000: ii; 2001: 61).

Menegazzia dielsii is characterised by: the corticolous habit; pruinose apothecial discs; a densely granular epithecium; 8-spored asci; ellipsoidal or oval ascospores, 30–40(–42) × 20–23(–26) μm, the walls 2 μm thick; and atranorin, psoromic (K+ yellow), conpsoromic and echinocarpic acids as secondary compounds. It is the only species of the genus in New Zealand with pruinose apothecial discs. Occasionally the pruina is poorly developed but is usually present on discs of young apothecia. It is also the only species of the genus in New Zealand with psoromic acid in the medulla (K+ yellow). The epithecium is densely granular as in M. lucens; however, the UV− medulla and the 8-spored asci distinguish it from this species. An undescribed taxon with pruinose apothecial discs and containing stictic, constictic and galbinic acids is known from Mt Cargill, Cascade Cove (Fiordland) and Stewart I. (Mt Anglem, Glory Cove) [unpublished observations].