Flora of New Zealand Series

=Sagenidium citrinum Follmann, Bot. Jber 96: 45 (1975).

Lectotype: New Zealand. Near Wellington, J. Buchanan – GLAM [fide Galloway (1985a: 519)].

Sagenidium citrinum. Holotype: New Zealand. Canterbury, Arthur's Pass National Park, Woolshed Hill, 1400 m, L. Visch C 62 – BM. Isotype – KASSEL.

Description : Flora (1985: 518).

Chemistry : Lepraric acid ±schizopeltic acid.

N: Northland (Radar Bush, Warawara State Forest), South Auckland (Kuratau, Moerangi, King Country), Gisborne (Lake Waikareiti), to Wellington (Tararua Ra.). S: Nelson (Kakapo Saddle Whangapeka Track, Burgoo Stream, Mt Herbert, Cobb Valley, Fyfe River, St Arnaud Ra., Flora Saddle Mt Arthur Ra.), Canterbury (Arthur's Pass), Otago (Leith Saddle, Blue Mts), Southland (Percy Saddle, Lake Manapouri, Monowai, Longwood Ra., Bluff Hill). St: (Ulva I., Fraser Peaks Magog, Islet Cove Port Pegasus). An epiphyte of mature forest trees, e.g. Dacrycarpus, Podocarpus and Nothofagus, where it is found typically on the undersides of inclined trunks or large branches in dry, overhanging habitats protected from direct contact with rain or water runnels, a particular ecology that is shared by a number of lichen genera including Bactrospora, Chaenotheca and Lecanactis, and by a number of byssoid lichens elsewhere (see Rogers & Hafellner 1987; Kantvilas 1996). Also known in Tasmania and Victoria (Kantvilas et al. 1985; Kantvilas & James 1987; Kantvilas 1989, 1994b, 2004j; Kantvilas & Minchin 1989; Jarman et al. 1991; Jarman & Kantvilas 1994; Filson 1996; McCarthy 2003c, 2006). A specimen (CHR 507158) collected by David Glenny from Branch Hut, Fyfe River, is from a dry marble wall in Nothofagus menziesii forest.

Australasian

Exsiccati : Moberg (1989: No. 72; 1999: No. 287); Vězda (1997c: No. 275).

Illustrations : Henssen et al. (1979: 265, pl. 1C; 266, pl. 2A, B, E – as Sagenidium citrinum); Kantvilas (1994b); Egea & Torrente (1994: 178, pl. 20, figs A–G); Malcolm & Galloway (1997: 140); Kantvilas & Jarman (1999: 140–141); Lumbsch et al. (2001: 40); Kantvilas (2004j: 200, fig. 8).

Sagenidium molle is characterised by: the corticolous habit; the grey-white or bluish-grey, spreading, byssoid thallus [becoming distinctly yellowish on storage in the herbarium in some specimens – the taxon S. citrinum illustrates this]; lecideine, plane black apothecia with densely white-pruinose discs; 5-septate ascospores, 22–30(–35) × 3–8 μm; and lepraric acid as the major chemical compound. It is distinguished from Roccellinastrum neglectum in its morphology (spreading rosettes rather than discrete lobes), ecology (dry underhangs on trunks and large branches of mature forest trees), chemistry and ascospores. Tasmanian populations of Sagenidium molle are parasitised by the lichenicolous fungus * Arthonia sagenidii Vězda & Kantvilas ntvilas & Vězda 1992), but to date this has not been noted from New Zealand populations.