Images of British Lichens
Usnea florida (L.) Weber ex F.H. Wigg.
Fruticose, tufted, much branched, yellow-green to grey-green, black at base of main stem, the main stem just above the base with fine, transverse but not longitudinal cracking, branches not constricted at their bases, terminal branches with small tubercles but lacking soralia and isidia; apothecia common, conspicuous, ringed by radiating fine branches which are entirely smooth, lacking soralia and isidia. Widespread but now rare in South-West England and Wales, very rare elsewhere and scarcely reaching Scotland, on branches, often in the tree canopy, and sometimes on fence posts.
Refs: Nordic Lichen Flora (2011) 4: 118, 168 (photos, printed too dark); James (2003), 21 (line illustrations); Smith et al. (2009), 925; Purvis et al. (1992), 626; Dobson (2005), 444-5 (photo); Dobson (2011), 451 (photo); Jahns (1983), 188-9 (photo); Whelan (2011), 149 (photo); van Haluwyn et al. (2009), 124-5 (photos); Valcárcel et al. (2003), 370-1 (photo); Wirth (1995), 2: 942, 947 (photo); Wirth et al. (2004), 39 (photo); Wirth, Hauck & Schulz (2013), 2: 1131 (photo), 1133; Frahm et al. (2010), 163 (photo); Moberg & Holmåson (1984), 107 (photo); Holien & Tønsberg (2008), 66 (photo); Arup et al. (1997), 237 (photo); Thor & Arvidsson (1999), 337 (photo), 514.
Easily and much confused with the fertile state of the closely related U. subfloridana (q.v.), but differs by its neater appearance with apothecia held above the rest of the thallus, and lack of soredia and isidia on the branches radiating from the apothecia. Interpretation of these two species is maintained here on traditional mophological concepts.
|On Sessile Oak (Quercus petraea), Ty Canol, Pembrokeshire, May 2009|
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Uploaded May 2009, last updated September 2013