Topeliopsis decorticans
Synonyms
Thelotrema decorticans, Thelotrema periphysatum
Family
Graphidaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Crustose
Current conservation status
2018 | Data Deficient | Qualifiers: SO
Brief description
Characterised by the muscicolous/corticolous habit; the pale grey-white, thin, somewhat arachnoid thallus; sessile to semi-immersed Geaster-like apothecia with thick, cracked, exfoliating margins obscuring disc apart from the central pore; 8-spored asci; broadly fusiform, colourless, muriform ascospores, 35–60 × 12–20 μm; and a negative thallus chemistry.
Distribution
North Island: Auckland (Rangitoto Island, Waitakere Ranges), Wellington (Kapiti Island).
Known also from Tasmania and Australia.
Habitat
Among bryophytes on fibrous bark.
Detailed description
Thallus pale grey-white, very thin, dull, or shining and ± varnish-like in places, arachnoid or lacking in parts, elsewhere rather granular or subverrucose or irregularly cracked, in irregular patches to 4 cm diam. Apothecia ± sessile or semi-immersed, 0.5-1.5 mm diam., margins thick, cracked, coarse, pulverulent exfoliating, Geaster-like, often obscuring disc, concolorous with thallus, pore 0.2-0.6 mm diam., disc pale pinkish-buff or whitish, granular. Hymenium colourless 102-120 µm thick. Ascospores 8 per ascus, colourless, muriform, broadly fusiform-ellipsoid, apices rounded or slightly pointed, (35-)50-60 × 12-15(-20) µm.
Chemistry: TLC–; four unidentified compounds.
Similar taxa
Thelotrema subdenticulatum (q.v.) is macroscopically indistinguishable but has transversely 19–26-septate ascospores.
Substrate
Corticolous, muscicolous
Topeliopsis is a rather heterogeneous genus included in the family Thelotremataceae (Eriksson et al. 2004; Pennycook & Galloway 2004), for taxa with sessile, exfoliating, perithecioid apothecia, with a cupular, usually brown-pigmented exciple, very well-developed periphyses, a persistently and deeply urceolate disc, markedly apically thickened asci (when young) and very large, thin-walled, colourless ascospores turning reddish or purple in KI.
Attribution
Fact sheet prepared by Melissa Hutchison (3 September 2021). Brief description, Distribution, Habitat, Features, Similar taxa, and Extra information sections copied from Galloway (1985, 2007).
References and further reading
Eriksson O.E., Baral H.-O., Currah R.S., Hansen K., Kurtzman C.P., Rambold G. & Laessøe T. 2004: Outline of Ascomycota – 2004. Myconet 10: 1-99.
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.
Pennycook S.R. & Galloway D.J. 2004: Checklist of New Zealand “Fungi”. In: McKenzie, E.H.C. (Ed.) Introduction to fungi of New Zealand. Fungi of New Zealand/Ngā Harore o Aoteroa Volume 1. Fungal Diversity Research Series 14: 401-488.