Flavoplaca citrina
Synonyms
Verrucaria citrina Hoffm., Caloplaca citrina (Hoffm.) Th.Fr.
Family
Teloschistaceae
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
Distribution
North Island: South Auckland (Coromandel Peninsula, Te Aroha), Taranaki (Waitara). South Island: Canterbury (Weka Pass, East of Tekapo, Dashing Rocks, Timaru), Otago (Miller’s Flat Cemetery, The Nuggets), Southland (Sharks Tooth near Forest Hill).
A widespread species in the Northern Hemisphere from the Arctic to the Mediterranean and North Africa, Israel, Ukraine, India, Asia, North America and Hawai’i. In the Southern Hemisphere it is known from Chile, Argentina, Australia and Antarctica.
Habitat
Throughout, on concrete posts, paths and walls (it is an early coloniser of concrete paving stones, often with Candelariella vitellina, Lecanora dispersa and Sarcogyne regularis), and on asbestos-cement cladding on walls and roofs, often forming extensive swards on these latter steeply sloping to vertical substrata; also on limestone and basic sandstone outcrops, occasionally on old leather (abandoned on dry inland soils), clay banks and on seashore rocks. In the Northern Hemisphere it is common on exposed calcareous and non-calcareous rocks (both coastal and inland), on concrete, soil, decorticated wood, lignum, dust-impregnated bark and occasionally over bryophytes.
Detailed description
Thallus crustose, effuse, coarsely granular-sorediate in a ± diffract-areolate crust, or ± thinly scattered, yellow to pale lemon yellow or green-yellow, K+ purple, saxicolous. Apothecia rather rare, 0.2-0.6 mm diam., disc plane, matt, orange, thalline margin granular, concolorous with thallus, occluded with age. Ascospores biseriate, ellipsoid with rounded ends, straight, 10-15 × 4.5-8 µm, septum c. ⅓ length of spore.
Chemistry: Soredia K+ violet-red; containing emodin, parietin, fallacinol, fallacinal, xanthorin and erythroglaucin.
Similar taxa
It seems likely that C. citrina as currently circumscribed comprises several distinct species and taxa of lower ranks.
Substrate
Saxiocolous, lignicolous, muscicolous, artificial substrates (concrete)
Attribution
Fact sheet prepared by Marley Ford (12 February 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.