Leptogium aucklandicum
Synonyms
Leptogium azureum, sensu D.J.Galloway (1985)
Family
Collemataceae
Flora category
Lichen – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Lichens - Foliose
Current conservation status
2018 | Not Threatened
Brief description
Characterised by the corticolous habit; the distinctive blue to blue-grey colour, the large, rather thin lobes with entire, undulate margins, the absence of isidia, and of tomentum on the lower surface.
Distribution
North Island: Northland (Kaipara) to Wellington (Kaitoke). South Island: Marlborough (Onamalutu) to Southland (Dusky Sound, Riverton). Stewart Island: (Glory Cove). Campbell Island.
Habitat
Rather rare, mainly in wetter western areas where it grows among mosses on trunks and branches of trees and shrubs, also rarely foliicolous, and on mossy rocks in grassland, both East and West of the Main Divide, s.l. to 1000 m.
Detailed description
Thallus submonophyllous to polyphyllous, dark grey-blue to distinctly bluish when wet, dark leaden grey or slate-grey when dry, 2–10 cm diam., attached to substratum by scattered tufts of hairs, loosely attached, corticolous, muscicolous. Lobes rather papery, orbicular to elongate, apices rounded, 2–8(–15) mm broad, margins sinuous, entire to sublobulate. Upper surface smooth to somewhat roughened, never wrinkled–plicate, without isidia or phyllidia. Lower surface concolorous with upper surface, without tomentum. Apothecia common, often abundant, to widely scattered, or occasionally absent, sessile to shortly pedicellate, laminal, 0.2–1.0(–2) mm diam., disc concave to plane or subconvex, pale orange-brown to red-brown, matt, proper exciple rarely seen, thalline exciple entire, thin or with occasional small, microphylline outgrowths, concolorous with thallus or paler, often creamish white. Epithecium orange or yellow-brown, 12.5–15 μm thick. Hymenium colourless, 90–115 μm tall. Hypothecium opaque, pale brownish. Ascospores broadly ellipsoidal, apices distinctly pointed, submuriform, with 3–7 transverse septa and 1–3 longitudinal septa, not constricted at septa, (20–)25–27.5(–32.5) × 10–12.5(–15) μm [Zahlbruckner (1941) gives 20–24 × 5.5–7 μm].
Similar taxa
Verdon (1992) records “… Many past and recent determinations of L. azureum from south-eastern Australia and N.Z. are misdeterminations of Collema subconveniens (blue-grey form)…”, and care is needed to distinguish this Collema from specimens of L. aucklandicum. Young apothecia of C. subconveniens are commonly clustered together in ±erumpent groups, the thalline margins only slightly raised above the level of the thallus. The spores of C. subconveniens are longer, 20–40(–43) μm (and more noticeably apiculate at the apices), and also broader, 8–10.5(–15) μm, and are distinctively constricted at the transverse septa than are those of L. aucklandicum, and generally have mainly 2 and not 3 longitudinal septa for each transverse septum (Degelius 1974).
Substrate
Corticolous, muscicolous, rarely foliicolous
Attribution
Fact sheet prepared by Marley Ford (5 August 2022). Brief description, Distribution, Habitat, and Features sections copied from Galloway (2007).
References and further reading
Degelius G. 1974: The lichen genus Collema with special reference to the extra-European species. Symbolae Botanicae Upsalienses 20(2): 1–215.
Galloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.
Verdon D. 1992: Leptogium. Flora of Australia 54: 173–192.
Zahlbruckner A. 1941: Lichenes Novae Zealandiae a cl. H.H.Allan eisque collaboratoribus lecti. Denkschriften der Akademie der Wissenschaften in Wien mathematisch-naturwissenschaftliche Klasse 104: 249–380.