Graphis marusae
Graphis marusae is a species of corticolous crustose lichen in the family Graphidaceae. It is found in a relict tropical lowland rainforest in Veracruz, Mexico, growing in exposed understory.
Taxonomy
The lichen-forming fungus was described as new to science in 2011 by the lichenologists Alejandrina Peña and Robert Lücking. The type specimen was collected by Bárcenas Peña from the Los Tuxtlas Biosphere Reserve at an elevation of, where it was growing in a lowland rainforest on the bark of Astrocaryum mexicanum and Pseudolmedia oxyphyllaria. It is characterised by its green thallus, its 1–5 mm-long with grey-black labia.Description
The thallus of Graphis marusae reaches up to in diameter with a thickness of 50–100 μm. The surface of the thallus is smooth, shiny, and pale greenish-grey in colour. There is no prothallus. In cross-section, the thallus has a upper cortex, an irregular, and clusters of crystals.The apothecia of Graphis marusae are and, typically unbranched, and prominent on the surface. They measure 1–5 mm in length, 0.2–0.3 mm in width, and 0.2–0.25 mm in height. The of the apothecia is concealed, with a thick that initially remains smooth but eventually becomes striate. The is indistinct, thin, and ranges from basal to almost lateral, greenish-grey in colour. The grey-black labia are almost fully exposed.
The is completely, measuring 80–120 μm in width, and can be entire to apically . The excipulum is basally covered by a thin layer of the thallus. The is, 10–20 μm high, and colourless. The hymenium is 100–150 μm high, colourless, and clear, while the is indistinct.
The paraphyses are unbranched. The asci are, measuring 90–120 by 25–35 μm. Each ascus contains 8 ascospores, which are oblong, 9–13-septate, measuring 50–70 by 10–15 μm, and are 4–5 times as long as they are wide. The are colourless. No secondary metabolites were detected in Graphis marusae using thin-layer chromatography.