Trapelia coarctata
Synonyms
Lichen coarctatus, Lecidea coarctata var. exposita Nyl., Lecanora coarctata var. exposita (Nyl.) Nyl.
Family
Trapeliaceae
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 smooth, uniform, to minutely areolate, pale-greenish to brownish thallus; the small, scattered, pale red-brown, epruinose, subinnate to emergent, sessile apothecia, with an adhering pseudothalline margin derived from its eruption through the thallus; and ellipsoidal ascospores, 14–17(–21) × 7–10 μm.
Distribution
North Island: Northland (Three Kings Islands, Little Barrier Island), Auckland (Waitakere coast), South Auckland (Motuhora Island), Wellington. South Island: Marlborough (Ship Cove), Canterbury (Hawdon River), Otago (Old Man Range, Lake Onslow, Mt Teviot, Moa Flat, Rock & Pillar Range, Leith Valley, Mt Cargill, “Green Island Bluff”, Southland (Lake Monowai, Blackmount near Clifden). Stewart Island: (Deceit Peaks).
Known also from Great Britain, Europe, Scandinavia, Morocco, Turkey, North America, Venezuela, Brazil, Chile, India, Japan, Indonesia, Marion Island, South Georgia, South Shetland Islandss, and Australia.
Habitat
On rocks and soil, coastal and inland, on exposed soil in eroded tussock grassland, and on depleted grassland soils associating with Cladia inflata agg., Diploschistes muscorum ssp. bartlettii, Endocarpon pusillum, Siphula coriacea, Xanthoparmelia semiviridis; often on recently exposed roadside cuttings or slips, commonly associating with sorediate species of Placopsis.
Detailed description
Thallus rather smooth, green-white, grey or brown often tinged pinkish, continuous, cracked-areolate or with areolae dispersed and ± squamulose at margins. Apothecia 0.2-2 mm diam., round, scattered, disc red-brown to brown- black, ± roughened, sometimes with a pseudothalline margin caused by its eruption through the thallus, part of which may remain adhering. Ascospores ellipsoid, 14-17 × 7-10 µm.
Chemistry: Thallus K−, C+ red, KC−, Pd−; containing gyrophoric acid.
The lichenicolous fungus *Sphaeria sociella was described as a parasite of T. coarctata. It has scattered, globose to pyriform, black perithecia, 100–200 μm diam.; 4-spored asci; and colourless, thin-walled, 1–3-septate ascospores, 10–12(–15) × 3–4 μm.
Similar taxa
It is closely related to Placopsis but differs mainly in the absence of cephalodia.
Substrate
Saxicolous
Attribution
Fact sheet prepared by Marley Ford (3 November 2021). Brief description, Distribution, Habitat, and Features sections copied from Galloway (1985) & Galloway (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.