Flora of New Zealand Series

≡Lecanora versicolor Hook.f. & Taylor, Lond. J. Bot. 3: 642 (1844).

≡Psoroma versicolor (Hook.f. & Taylor) Müll.Arg., Flora 71: 534 (1888).

≡Psoromidium versicolor (Hook.f. & Taylor) D.J.Galloway, N. Z. J. Bot. 21: 196 (1983).

Lectotype: New Zealand. Lord Auckland's Group, on live wood, J.D. Hooker 1572 – BM [fide Galloway (1983a: 197)]. Isolectotypes – FH, G.

Description : Flora (1985: 484 – as Psoromidium versicolor). See also Galloway & James (1985: 180–183).

Chemistry : TLC−, all reactions negative.

S: Westland (Alexander Ra. Camp Creek). St: (Track from Disappointment Cove to Broad Bay) on bark of Myrsine australis, together with Degeliella rosulata, Megalaria pulverea, Menegazzia nothofagi, Pannaria immixta, P. sphinctrina. A: (Erebus Cove, Terror Cove, Laurie Harbour). On bark of Fuchsia, Metrosideros umbellata, Myrsine australis, Neopanax and Weinmannia racemosa, lowland, coastal (see Setzepfand & Sipman 2004 – as Psoromidium versicolor). Known also from Tasmania and southern South America (Galloway & James 1985: 184; McCarthy 2003c, 2006; Jørgensen 2004a).

Austral

Illustrations : Galloway & James (1985: 181, fig. 3; 182, fig. 4); Hawksworth (1985b: 299, fig. 1A); Jørgensen & Galloway (1992b: 292, fig. 99B); Kantvilas & Jarman (1999: 137) – all as Psoromidium versicolor.

Degeliella versicolor is characterised by: the corticolous habit; a thallus of flattened, scattered to contiguous squamules dispersed on a thin, furfuraceous prothallus; flattened or convex, plicate–radiate cephalodia with prominent, whitish, radiating striations when moist; discrete, rarely conglomerate apothecia with prominent, persistent margins; ascospores distinctly roughened–warted, spherical to oval–ellipsoidal, 9–12(–15.5) × 4.5–9(–13) μm. Some Tasmanian collections of P. versicolor are parasitised by Polycoccum jamesii D. Hawksw. (Hawksworth 1985b), and this parasite (q.v.) occurs also on Port Pegasus populations of D. versicolor.