Arthrorhaphis alpina
Common name
Alpine dot lichen
Synonyms
Lecidea flavovirescens var. alpina
Family
Arthrorhaphidaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Crustose
Current conservation status
2018 | Not Threatened | Qualifiers: SO
Brief description
Characterised by the compact, squamulose-lobate (often hollow at the apices) thallus which is generally free of soredia (except in some sheltered situations), by calcium oxalate crystals in the medulla, by shorter acicular ascospores than A. citrinella, the ascospores generally not lying at the same height in the ascus.
Distribution
North Island: Wellington (Mt Ruapehu). South Island: Nelson (Mt Arthur, St Arnaud Ranges, Wairau Valley), Canterbury (Mt Sebastopol), Otago (N Huxley Valley, Mt Cargill). Campbell Island: (Mt Honey, Mt Lyall).
Widely distributed in the Northern Hemisphere where it is a circumpolar, arctic-alpine species. It has a rather restricted occurrence in the Southern Hemisphere being known from alpine regions of New South Wales in Australia, from Tasmania, Mt Wilhelm in Papua New Guinea in summit tundra at 4900 m, from Hawai’i and from the E coast of the Antarctic Peninsula. Recently reported from Campbell Island, and the South Shetland Islands.
Habitat
On soil in alpine fellfield.
Detailed description
Thallus squamulose-lobulate, irregularly spreading, 0.5–3(–5) cm diam., muscicolous-terricolous. Squamules 0.2–5 mm diam., round to irregular, convex, swollen, scattered, discrete to ±crowded-congested, plicate, ±cerebriform or areolate-imbricate, often hollow in apical parts, vivid yellow-green, yellow to sordid yellow-brown or ±blackened in parts, surface matt, somewhat roughened, minutely crazed with fine black lines (×10 lens), soredia generally absent, present in some specimens from sheltered habitats. Apothecia moderately common, sessile, 0.5–3 mm diam., solitary to 5–6-conglomerate, developed at margins of squamules, or sometimes in discrete, scattered clumps independent of thalline squamules, round to somewhat irregular, at first slightly immersed between squamules, soon becoming convex and at maturity ±convex-convolute and projecting above squamules, marginate at first, then immarginate, disc black, matt, epruinose, slightly roughened, plane at first, soon convex and at maturity markedly rugose-plicate. Epithecium densely granular, greenish black, pigment dissolving in K, 25–35 μm thick. Hymenium 124–145 μm tall, opaque, appearing finely granular, pale straw-coloured to grey-brown. Asci narrowly clavate, tapering at foot, 90–145 × 9.11.5 μm. Ascospores colourless, 7–12(–14)-septate, acicular, apices tapering, pointed (55–)60–75(–85) × 2.5–4 μm.
Chemistry: Rhizocarpic acid, epanorin and unidentified pigments.
Similar taxa
Has shorter acicular ascospores than Arthrorhaphis citrinella.
Substrate
Terricolous
Etymology
alpina: From the Latin alpes ‘the Alps’, refers to plants growing in mountainous areas
Attribution
Fact sheet prepared by Melissa Hutchison (29 December 2021). Brief description, Distribution, Habitat, and Features sections copied from Galloway (1985, 2007).
References and further reading
Galloway D.J. 1985: Flora of New Zealand: Lichens. Wellington: PD Hasselberg, Government Printer. 662 pp.
Galloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.