Flora of New Zealand Series

≡Lichen carnosus Dicks, Fasc. pl. cryptog. brit. 2: 21 (1790).

Description : Thallus rosette-forming, to irregularly spreading, 0.5–2(–4, rarely to 8) cm diam., muscicolous rarely terricolous. Lobes to 0.1–2 mm wide, 1–3 mm long, irregularly finger-like to ±flabellate. Margins conspicuous, thickened or swollen, often raised, irregularly incised or ±pectinate; sparsely to densely phyllidiate, eroding of fractured phyllidia exposing medulla and margins appearing frosted–tomentose. Upper surface uneven, minutely lumpy to unevenly ridged, glaucous brown to greyish red-brown to grey-blue when moist (tips of phyllidia persistently grey-brown), paler red-brown to brown when dry; phyllidiate, maculate, without soredia. Phyllidia short, gnarled glomerulate to ±coralloid, slightly expanded at apices, 0.1–1 mm tall and 0.1–0.3 mm wide, terete to flattened, often densely developed in a diffract marginal and laminal crust. Maculae white, irregular to reticulate, best seen in moist thalli (×10 lens). Lower surface decorticate, ±arachnoid, grey-brown in a narrow marginal band grading into a wider whitish zone becoming pale yellow-brown to brownish centrally, attached to substratum by short, rather diffusely scattered pale to brownish rhizohyphae (see Reinke 1895: 438, fig. 155). Thallus c. 100 μm thick in section with a distinct 3-layered cortical layer to 25 μm thick of isodiametric cells to 10 μm diam., upper part distinctly brown-pigmented. No lower cortex. Medulla prominent, consisting of large clumps of Nostoc, individual cells 5 μm diam., interwoven with hyphae. Apothecia sparse to numerous, often obscured by tips of phyllidia, widely scattered to 4–6-confluent and then distorted through mutual pressure, laminal, sessile to subpedicellate, 0.1–1.5(–2) mm diam., plane to subconcave; disc red-brown with a slightly darker marginal zone when moist, dark red-brown to dark-brown with pale, paraplectenchymatous proper margin (to 120 μm wide) when dry, matt, epruinose. Hypothecium colourless, 40–80 μm thick, of intricately woven hyphae. Thecium to 110 μm tall, I+ deep blue, upper part brown-pigmented. Asci cylindrical, 50–70 × 10–15 μm. Ascospores colourless 1-septate, narrowly ellipsoidal constricted at septum, 20–25 × 5–6(–8.5) μm, lumina often vacuolate and appearing 3-septate.

Chemistry : TLC−, all reactions negative.

N: Taranaki (Mt Taranaki). S: Canterbury (Arthur's Pass, Upper Godley Valley, Glen Lyon Station), Otago (Williamson River, Forgotten River, Rees Valley, Poolburn, Old Man Ra., Craig Flat, Timaburn Road to Lake Onslow, Mt Maungatua, Lammerlaw Ra., and Swampy Summit near Dunedin) but probably more widely distributed than present records show. Among mosses (Andreaea, Racomitrium) on boulders and sloping rock faces (usually in small drainage and seepage channels and rock joints and ledges where mosses trap moisture), easily overlooked. Associating with Bartlettiella fragilis, Coccocarpia palmicola, Collema durietzii, Lepraria neglecta, Pseudocyphellaria crocata, Siphulastrum spp., Steinera neozelandica and Toninia bullata. Circumpolar in the Northern Hemisphere where it is most frequently found in subalpine regions where there is sufficient moisture (Henssen 1963a; Purvis et al. 1992; Nimis 1993; Santesson 1993; Goward et al. 1994b; Esslinger & Egan 1995; Scholz 2000; Diederich & Sérusiaux 2000; Gilbert 2000; Brodo et al. 2001; Burgaz & Martínez 2001; Hafellner & Türk 2001; Llimona & Hladun 2001; Coppins 2002b; Nash 2002a; Nimis & Martellos 2003; Santesson et al. 2004). Also circumpolar in subalpine to alpine regions of the Southern Hemisphere where it is known from New Zealand, SE Australia, Marion I., Kerguelen, the Antarctic Peninsula, Charcot I., the South Shetland Is, South Georgia, the South Orkney Is, the Falkland Is and Bouvetøya (Jørgensen & Elix 1988; Convey et al. 2000; Øvstedal & Gremmen 2001; Øvstedal & Lewis Smith 2001; McCarthy 2003c, 2006; Wirtz et al. 2003; Søchting et al. 2004).

Bipolar

Illustrations : Reinke (1895: 438, figs 154, 155); Moberg & Holmåsen (1982: 169); Wirth (1987: 277; 1995a: 569); Dobson (1992: 199; 2000: 226; 2005: 258); Goward et al. (1994b 73, fig. 3B); Hansen (1995: 41); McCune & Geiser (1997: 155); Brodo et al. (2001: 428, pl. 489); Wirtz et al. (2003: 179. fig. 2B).

Massalongia carnosa is easily overlooked as it grows among mosses (frequently associating with species of Racomitrium) and has a similar colour. Often it is mistaken for a member of the Pannariaceae. When fertile it is readily recognised by the characteristic, narrowly ellipsoidal, 2-celled spores that are unknown in the Pannariaceae. In Australasia it is most likely to be confused with Parmeliella thysanota, but this latter species has a more foliose appearance, is normally pale grey-blue, and produces apothecia with simple spores. Small species of Pannaria also could be confused with M. carnosa, but they have apothecia with a thalline margin, are squamulose to subcrustose, and usually grow directly on rocks or soil.