Dimerella lutea (images of British lichens)

Thallus thin, effuse, scurfy to somewhat granular, grey or green-grey; apothecia fleshy, to 2mm in diameter, yellow to orange with paler margins, contracted at the base. Predominantly western, in humid situations, typically on damp bark or overgrowing mosses. If the thin thallus is not noticed, the apothecia could be taken to be one of the non-lichenised cup-fungi, e.g. a species of Hymenoscyphus, or, conversely, species of Hymenoscyphus, notably H. calyculus, might be taken to be this species.

Refs: Smith et al. (2009), 377; Purvis et al. (1992), 235; Dobson (2005), 163-4 (photo); Dobson (2011), 170 (photo); Jahns (1983), 254-5 (photo); Whelan (2011), 92 (photo); Holien & Tønsberg (2008), 202 (photo); Thor & Arvidsson (1999), 262 (photo); Arup et al. (1997), 177 (photo); Wirth (1995), 1: 375-6 (photo); Wirth, Hauck & Schulz (2013), 1: 418 (photo, as Coenogonium luteum); Frahm et al. (2010), 51 (photo, as Coenogonium luteum); Puntillo (1996), plate 16 (photo); Valcárcel et al. (2003), 182-3 (photo); Brodo et al. (2001), 302 (photo).

FGBI: http://fungi.myspecies.info/all-fungi/dimerella-lutea

lastdragon.org

Images of British Lichens