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Page number:324 
Remarks (internal):Graphis cristobalensis is characterised by conspicuous, sessile, open lirellae, small 4-locular ascospores and the presence of testacein. This compound is uncommon in the Graphidaceae and is found in Graphina allosporella (Nyl.) Müll. Arg. (Nylander 1869), G. sphaerosporella (Nyl.) Müll. Arg. (Nylander 1869) and Platythecium acutisporum Staiger (Staiger 2002). The new species is distinguished from the two Graphina species by the 4-locular ascospores, and from the Platythecium species by terminally rounded ascospores. In addition, the exciple in G. cristobalensis is pale brown, in contrast to that of P acutisporum which is carbonised. The new species is so far known only from two specimens, from the same locality, with the same collector's number 
Description type:Original description 
Description:Graphis cristobalensis A.W. Archer, sp. nov. Figure 3
Type: Solomon Islands. Makira Province. San Cristobal Island, N of Ugi Island, near Pawa School, ca. 1/2 mile [ 0.8 km] along path inland and into jungle, alt. ca. 50ft [I5 m], J.D.. Hill 8706, 12.viii.1965; holotype: BM.
Key characters - Thallus pale fawn, corticolous, surface smooth and shiny. Apothecia lirelliform, conspicuous, sessile in irregular clusters ca. 3 x 4 mm, individual lirellae 0.25-0.4 mm wide, with a conspicuous, raised, white thalline margin. Epithecium pale grey, fine white-pruinose. Exciple complete, thin, pale reddish brown, Hymenium 100-120 µm tall, pale brown, not inspersed, I-ve. Ascospores 8 per ascus, elongate-ellipsoid, hyaline, 13-16 µm long, 5-6 m wide, 4-locular, I± pale blue.
Chemistry - testacein.
Ecology Graphis cristobalensis is an uncommon corticolous species found at sea-level at ca. 15 m elevation in secondary and disturbed primary rainforest on San Cristobal Island.
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