Thalloloma Trevis.
Type : Thalloloma anguinum (Mont.) Trevis. [=Ustalia anguina Mont.]
Description : Flora (1985: 172 – as Graphina Müll.Arg.).
Thalloloma is a cosmopolitan genus of c. 205 species, formerly treated as Graphina (Staiger 2002), included in the family Graphidaceae (Staiger 2002; Eriksson et al. 2004; Pennycook & Galloway 2004) and most widely recorded from tropical areas. The generic division of the mainly tropical family Graphidaceae, until very recently, was based on the concept of spore genera of Müller Argoviensis (1880, 1882), who distinguished the genera Graphina, Graphis, Phaeographina and Phaeographis using ascospore colour (brownish or hyaline) and ascospore septation (transversely septate or muriform). This was considered an artificial concept, and until very recently no attempt was made to establish a new generic disposition representing natural groups. Staiger (2000) indicated that a more natural disposition may be arrived at using characters such as excipular structure, paraphyses, ascospore type and chemistry, and suggested that earlier generic names such as Dyplolabia A.Massal., Fissurina Fée and Thalloloma Trevis. could be reinstated, a position she now formally adopts (Staiger 2002) and which is followed here. Useful information (under Graphina) is found in the earlier, spore-based literature (Redinger 1933a, 1933b, 1936a; Magnusson 1955; Wirth & Hale 1963, 1978; Nakanishi 1966; Hayward 1977; Makhija et al. 1992a; Archer 1999b, 2001a, 2001e, 2002; Nakanishi et al. 2001). One species is known from New Zealand (Galloway 2004c: 118). Two species formerly included in Graphina (Galloway 1985a: 172–173) are now referred to Fissurina (q.v.).
