Siphulella, a New Lichen Genus from Southwest Tasmania

Abstract

The lichen genus Siphulella (Lichenised Ascomycotina, Helotiales, Baeomycetaceae) is described, based on the single species Siphulella coralloidea Kantvilas, Elix & James sp. nov. The genus is characterised by a dimorphic thallus, apothecia borne on podetia, eight-spored asci of the Baeomyces-type, and simple, hyaline ascospores. Its chemistry consists ofsiphulellic acid, a unique previously unknown 3-orcinol depsidone structurally related to psoromic acid. Siphulella is endemic to Tasmania where it occurs on soil, peat, and stones in treeless vegetation in high rainfall areas. Its relationships with the other genera of the Baeomycetaceae are discussed briefly. The present paper deals with a remarkable new macrolichen genus which appears to be endemic to southwest Tasmania. This is a wilderness region within the Tasmanian Wilderness World Heritage Area and is characterised by a rugged topography, high rainfall (to 3,400 mm per annum), and a pre- dominantly metamorphic, pre-Carboniferous ge- ology. Its vegetation consists of extensive areas of buttongrass moorland (dominated by a sedge, Gym- noschoenus sphaerocephalus) and cool temperate rainforest, as well as alpine formations and eucalypt forest, and includes a large proportion of Tasma- nia's endemic vascular flora. Recent investigations (e.g., Kantvilas & Jarman 1988, 1991) indicate that the cryptogamic flora of the region is also rich and distinctive and several interesting species are either confined to or attain their peak of development there (e.g., see Coppins & Kantvilas 1990; Galloway & James 1987; Henssen & Kantvilas 1985; Kantvilas 1987, 1990; Kantvilas & Elix 1987). The present new genus appears to be another such taxon.