Stereocaulon gregarium
Synonyms
Gymnocaulon gregarium
Family
Stereocaulaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Fruticose
Current conservation status
2018 | Not Threatened | Qualifiers: SO
Brief description
Characterised by the saxicolous habit; dwarf, simple, or bifurcating at apices, terete, corticate, finger-like podetia (fertile podetia commonly being taller than sterile podetia); the matt, wrinkled-verrucose grey-white cortex; the pale yellowish brown basal cephalodia; convex, immarginate apothecia, pale-yellowish or colourless hypothecium; 6–10-septate ascospores, 48–68 × 5–6 μm; and a chemistry of atranorin and protocetraric acid, with fumarprotocetraric, perlatolic, colensoinic and anziaic acids as inconstant accessory compounds.
Distribution
North Island: Taranaki (Mt Taranaki), Wellington (Mt Ruapehu, Ruahine Ranges, Tararua Ranges). South Island: Marlborough (Mt Stokes), Westland (Alec’s Knob), Canterbury (Arthur’s Pass, Torlesse Range), Otago (West Matukituki Valley, Stoneburn, Swampy Summit, Flagstaff, Abbott’s Hill, Maugatua), Southland (McKinnon Pass, Secretary Island, Mt Hodges, Dusky Sound, Borland Lodge). Stewart Island: (Mt Allen, Magog, Smith’s Lookout).
Australasian. Known also from alpine habitats in Tasmania.
Habitat
On exposed rocks in subalpine to alpine grassland.
Detailed description
Thallus to 15 mm tall, fertile pseudopodetia conspicuously taller than sterile pseudopodetia. Pseudopodetia simple, occasionally bifurcating at apices, terete, finger-like, corticate, cortex continuous, smooth to cracked, verrucose-wrinkled, whitish-cream never purplish-brown, exposed forms greyish, the result of a crazing of fine black lines across the cortex. Phyllocladia absent. Cephalodia basal, pale yellowish-brown or greenish, never black, distinctly cerebriform, convoluted. Apothecia terminal, often 2-3 per pseudopodetium, disc black, 1-4 mm wide, plane at first with a thin, pale margin, becoming convex and immarginate at maturity, thalline exciple smooth, pale yellowish-brown. Hypothecium colourless or pale yellowish-brown, 100-120 µm tall. Ascospores fusiform, acicular, 6-8(-10)-septate, 48-68 × 5-6 µm.
Chemistry: Atranorin and protocetraric acid, with fumarprotocetraric, perlatolic, colensoinic and anziaic acids as inconstant accessory compounds.
Similar taxa
Similar to Stereocaulon caespitosum, but that species has brown-black, scabrid cephalodia, and plane apothecia, which are distinctly marginate, and a colourless hypothecium; whereas S. gregarium has persistently pale, wrinkled-scrobiculate cephalodia, and convex, immarginate apothecia, and a brown hypothecium.
Substrate
Saxicolous
Attribution
Fact sheet prepared by Melissa Hutchison (16 June 2023). 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.