Usnea flavocardia
Synonyms
Usnea wirthii P.Clerc,
Family
Parmeliaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Fruticose
Current conservation status
2018 | At Risk – Naturally Uncommon | Qualifiers: DP, SO
Brief description
Characterised by the small shrubby thallus (it is a member of the U. fragilescens agg.); inflated branches, wide, sparse, yellow medulla; thin glossy cortex, sometimes with minute purplish red spots; plane to excavate soralia with granular to isidiose soredia; and two chemodemes (containing either norstictic acid K+ yellow→red; or psoromic acid K−, Pd+ golden-yellow).
Distribution
North Island: Wellington (Mt Lees Reserve near Palmerston North, Tararua Ranges, Makara Peak, Wellington City). South Island: Dunedin. Chatham Islands.
Known also from Europe, Western North America, Baja California, Mexico and Chile.
Habitat
On canopy branches of trees and shrubs in lowland forest and coastal scrub.
Detailed description
Thallus pale-green, erect, to 3 cm long, isotomic dichotomous, moderately branched, branches divergent, with one single point of attachment; trunk concolorous, short, 2 mm long, straight. Branches cylindrical, tapering slowly; segments terete, cylindrical to slightly swollen; apices short, finely branching. Surface papillate, fibrillose, sorediate; without pseudocyphellae; cortex glossy, often with small red spots (×10 lens) [these may be hard to find under the hand lens and even the dissecting binocular]. Papillae verrucose, sparse to abundant, irregularly scattered. Fibrils short, 1–2 mm long, spinulose, few to absent, mostly on main and secondary branches. Soralia on apices and short branches, originating in cortex or from transverse cracks, superficial to excavate, solitary to confluent; soredia granular to isidiose. Medulla thick, very loose to dense, fibrous, yellow. Axis thin, straight, solid, yellowish. Apothecia rarely present.
Chemistry: Cortex K+ yellow→red, C−, KC+ red, Pd+ golden-yellow; containing usnic, stictic, salazinic, norstictic and/or psoromic acids.
Similar taxa
Similar to Usnea cornuta but separated by its yellow medula and the presence of red cortical spots (×10 lens).
Substrate
Corticolous
Attribution
Fact sheet prepared by Marley Ford (16 Noverber 2022). Brief description, Distribution, Habitat, Features, and Similar taxa sections copied from Galloway (2007) (as U. wirthii).
References and further reading
Galloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.