Lobothallia radiosa
Synonyms
Lecanora allanii, Lichen radiosus
Family
Megasporaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Placodioid
Current conservation status
2018 | Not Threatened | Qualifiers: SO
Brief description
Characterised by the saxicolous habit (periodically or partially inundated rocks); a greyish, radiating, closely attached, rosette-shaped thallus; radiating plicate–lobate, marginal thalline lobes; ±central, clustered, immersed aspicilioid apothecia; paraphyses without moniliform apices; and subglobose to ellipsoidal ascospores, 10–12(–15) × 7–9 μm.
Distribution
North Island: Wellington (Manawatu Gorge, Ohau River). South Island: Nelson (Kaituna Gorge, Pelorus Bridge, Buller River), Canterbury (Porter’s Pass), Otago (Canyon Creek, Ahuriri River, Kawarau Gorge, Cromwell Gorge, Black Head), Southland (Gertrude Valley, Hollyford River, upper Mataura River, Waikaia River).
Still rather poorly known in New Zealand.
A widespread species in the Northern Hemisphere, known also from North America.
Habitat
On riverine rocks (often partly or periodically immersed), schist outcrops near rivers or streams, also on coastal rocks and in alpine greywacke talus at 1200 m. Associating with Candelariella vitellina, Physcia caesia, Placopsis ampliata, P. elixii, P. illita, P. perrugosa.
Detailed description
Thallus to 2 mm thick, margins lobate, placodioid-radiating, ± subfoliose, pale glaucous-grey or olivaceous, matt, distinctly and minutely white-maculate (×10 lens), areolate-cracked, cracks deep, radiating, areolae angular, plane, rosette-forming to irregularly spreading (1-)2-6 cm diam. Apothecia innate to sessile, 1-2 per areole, 0.1-0.8 mm diam., subconcave to plane, disc dark red-brown, matt, epruinose, margins raised, entire, concolorous with thallus. Epithecium not granular. Hymenium colourless, 120-140 µm tall. Paraphyses simple, dense, 2 µm diam., not thickened at apices, moniliform towards apices. Asci clavate. Ascospores biseriate, subglobose to ellipsoid 10.2-12 × 7-8.3 µm.
Chemistry: Variable, TLC−, or with norstictic acid.
Substrate
Saxicolous (rocks)
Attribution
Fact sheet prepared by Melissa Hutchison (2 March 2022). 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.