Flora of New Zealand Series

≡Parmeliella duplicata Müll.Arg., Flora 66: 78 (1883).

=Pannaria rubiginosa ssp. prolifera Nyl., Lich. Nov. Zel.: 48 (1888).

≡Pannaria rubiginosa var. prolifera (Nyl.) Müll.Arg., Bull. Herb. Boissier 2, App. 1: 43 (1894). [For additional synonymy see Galloway & Jørgensen (1987: 375–376)].

Pannaria rubiginosa ssp. prolifera. Lectotype: New Zealand. Sine loco [probably Wellington], 1867, C. Knight 4 – H-NYL 31313 [fide Galloway & Jørgensen (1987: 376)]. Isolectotype – WELT.

Description : Thallus forming rosettes to 5 cm wide. Lobes ±concave, subcanaliculate towards margins, 1–3(–5) mm wide, linear–laciniate. Margins raised, slightly thickened, sinuous, sometimes frosted–pruinose, phyllidiate. Phyllidia peltate–squamulose, rarely digitate, sometimes spreading onto upper surface and occasionally forming a thick, diffract, marginal crust. Upper surface markedy uneven but often glossy, and with conspicuous pale-brown apothecial initials, glaucous–olivaceous when wet, suffused red-brown at margins. Lower surface white at margins, brownish centrally, with densely clustered fascicles of silky, white to blue-black rhizohyphae, normally projecting beyond lobe margins. Apothecia rare, 0.1–1.5 mm diam., disc concave becoming plane, matt, epruinose, pale to dark red-brown with persistent paler, entire to shallowly sinuous proper exciple, slightly raised above disc. Hymenium I+ persistent blue. Ascospores 12–20 × 6–10 μm.

Chemistry : TLC−, all reactions negative.

N: Northland (Radar Bush, Te Paki Bush, Herekino Forest, Wairau Valley, Waipoua State Forest, Kawerua, Little Barrier I., Great Barrier I.), Auckland (Piha, Waitakere Ra.), South Auckland (Great Mercury I., Te Kauri Scenic Reserve near Otorohanga). In areas of high humidity and elevated summer temperatures, lowland, from s.l. to 920 m. Known also from Australia (New South Wales and Tasmania), New Caledonia and Norfolk I. (Galloway & Jørgensen 1987; Elix & McCarthy 1998; McCarthy 2003c, 2006). L. duplicatum is a corticolous species growing among bryophytes and other cyanophilic lichens (species of Coccocarpia, Erioderma, Leioderma, Pannaria, Parmeliella and Polychidium) on the phorophytes Kunzea ericoides and Leptospermum scoparium.

Palaeotropical

Illustrations : Galloway & Jørgensen (1987: 377, fig. 20A, B).

Leioderma duplicatum is characterised by: the corticolous habit; the long, subcanaliculate, marginally reddish-brown glabrous lobes; marginal to laminal phyllidia; and prominent development of rhizohyphae on the lower surface, often appearing like a prothallus.