Flora of New Zealand Series

≡Lecanora hagenii var. umbrina Ach., Lichenogr. universalis: 368 (1810).

=Lecanora hagenii auct. 

Description : Thallus thin to evanescent, pale grey-white. Apothecia scattered, sessile, rounded, 0.4–0.7 mm diam., disc brown, white-pruinose, margins thin, entire. Ascospores ellipsoidal, 7–14 × 4.5–7.5 μm.

Chemistry : TLC−, all reactions negative.

S: Canterbury (Kaitorete Spit), Otago (Tikoraki Point near Moeraki). On coastal sandstone rocks above high water mark and also on dead or decorticated branches of coastal shrubs. Known also from Great Britain, Europe, Scandinavia, and North America. (Brodo et al. 2001; Coppins 2002b; Laundon 2003; Nimis & Martellos 2003; Santesson et al. 2004).

Bipolar

Illustrations : St. Clair (1999: 98 – as Lecanora hagenii); Brodo et al. (2001: 381, pl. 422 – as Lecanora hagenii).

Lecanora umbrina is characterised by: the saxicolous/lignicolous habit; the K− evanescent thallus (forming small colonies), and the pruinose apothecia. It differs from L. dispersa in having, thin, neat, regular apothecial margins surrounding small, brown discs; and grows mainly on bark or decorticated wood. Formerly known as Lecanora hagenii (Ach.) Ach., a misapplied name (Laundon 2003: 98). Its relationship to L. dispersa needs further study (Laundon 2003: 98). However, Ryan et al. (2004b: 226) accept this taxon as L. hagenii, arguing that Laundon (2003) based his interpretation of L. hagenii var. umbrina on Acharian material under this name preserved in BM, whereas in the Acharius herbarium in Helsinki three varieties of the original Acharius collection are available [ var. cyanescens; var. umbrina; and var. syringea], and it is not certain that Laundon's interpretation of L. umbrina applies to all of the authentic Acharius material. L. hagenii  sensu Ryan et al. (2004b: 226) is based on the characters of var. cyanescens. The species is often parasitised by the lichenicolous fungus * Lichenoconium lecanorae (Jaap) D.Hawksw. (Hafellner 2000).