Heterodermia isidiophorella
Family
Physciaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Foliose
Current conservation status
2018 | Data Deficient
Brief description
Characterised by the diminutive thallus with very narrow lobes, the cylindrical, simple to sparingly branched isidia that become granular with age, the corticate lower surface with white to brown rhizines, and the presence of atranorin and triterpenes.
Distribution
North Island: Auckland North.
Australia (Queensland and New South Wales).
Habitat
Occurs on bark, twigs and, rarely, on rocks in coastal forest.
Detailed description
Thallus small-foliose, orbicular to irregularly spreading, adnate, 2–5 cm wide. Lobes 0.15– 0.5 mm wide, ±plane, sublinear-elongate, dichotomously or irregularly branched, ±discrete to contiguous at the periphery, with short lateral lobes; apices not ascending, eciliate. Upper surface whitish grey, isidiate; isidia laminal and marginal, cylindrical, simple to sparingly branched, eventually becoming granular and appearing sorediate. Medulla white. Lower surface corticate, white to pale tan or brown near the centre. Rhizines white, concolorous with the thallus or becoming pale to dark brown towards the apices, simple to irregularly branched, numerous, mainly marginal, 0.5–1.0 mm long, ±projecting beyond the lobe margin. Apothecia not seen. Pycnidia immersed; conidia bacilliform, 4–6 × 1 µm.
Chemistry: Cortex K+ yellow, C–, KC–, P+ yellow; medulla K+ yellow, C–, P–; containing atranorin (major), zeorin (major), 6α-acetoxyhopane-16β,22-diol (major), leucotylin (minor or trace), 16β-acetoxyhopane-6α,22-diol (trace), 6α-acetoxy-16β,22-dihydroxyhopane-25-oic acid (trace).
Similar taxa
Similar to Heterodermia isidiophora but a larger species (thallus 5–20 cm wide; lobes 0.7–2.5 mm wide vs thallus 2–5 cm wide; lobes 0.1–0.5 mm wide vs ) with isidia becoming granular.
Substrate
Corticolous, saxicolous
Etymology
heterodermia: From the Greek heteros (other, different) and derma (a skin or hide), in reference to the presence or absence of a lower cortex
Attribution
Fact sheet prepared by Marley Ford (3 January 2022). Brief description, Distribution, Habitat, Features, and Similar taxa sections copied from Elix (2011).
References and further reading
Elix, J. 2011. Further new species and new records of Heterodermia (Physciaceae, Ascomycota) from Australia. Australasian Lichenology 69: 12 -24.