Protoblastenia rupestris
Common name
Chewing gum lichen
Synonyms
Lichen rupestris
Family
Psoraceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Crustose
Current conservation status
2018 | Not Threatened | Qualifiers: RR, SO
Brief description
Characterised by the saxicolous (basicolous substrata) habit; the scurfy, areolate, greenish grey, grey-white to greenish brown or orange-grey thallus (often absent); sessile, to semi-immersed dull-orange, biatorine apothecia (K+ purple); and simple ascospores.
Distribution
North Island: Auckland (Henderson). South Island: Canterbury (Castle Hill), Southland (Sharks Tooth, Springhills near Forest Hill).
Known from Great Britain, Europe, the Canary Islands, Scandinavia, Greenland, Svalbard, the Balkans, Asia, North America, and Tasmania.
Habitat
Common on calcareous paving stones in and around Auckland, elsewhere on limestone.
Still very poorly known and collected in New Zealand. It should be searched for on limestone and other basicolous substrata such as mortar, cement, asbestos, concrete, and calcareous sandstone. In the Northern Hemisphere it is an important indicator of calcareous substrata and is often frequent in urban environments.
Detailed description
Thallus greenish-white to greenish-grey, smooth, irregularly cracked, often lacking or immersed. Apothecia sessile or subimmersed, 0.3-0.8 mmdiam., disc dull orange-red (K+ purple). Ascospores ellipsoid, simple, 8-15 × 5-8 µm.
Chemistry: Disc K+ purple; containing parietin, emodin, teloschistin, fallacinal and parietinic acid.
Substrate
Saxicolous
Etymology
rupestris: From the Latin rupes ‘rock, cliff’, meaning growing in rocky places
Attribution
Fact sheet prepared by Marley Ford (23 December 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.