Lichens marins

Description

Lichenicolous ascomycete fungus occurring on lichens of the genus Flavoparmelia.

Anamorph (= Vouauxiomyces truncatus (B. de Lesd.) Dyko & D. Hawksw.): Formed of usually abundant pycnidia, 0.1-0.2 mm in diameter, buried in the thallus of the host, slightly protruding and clearly visible by their superficial ostiole, widely open, black. Ovoid conidia with truncated base, hyaline, 5-8 x 3.5-4.5 µm according to the literature; 5-7 x 4-5 µm according to our measurements.

Teleomorph: Apothecia as if placed on the thallus of the host, 0.2 - 0.3 mm in diameter, flat disc then slightly convex, black. Epihymenium K+ green. Spores long elliptical, warty, brown, once septate delimiting 2 cells of unequal size (a little pestle), 10-14 x 4-5.5 µm according to the literature. Rare species occurring on Flavoparmelia caperata and Flavoparmelia soredians (would also sometimes be present, but very rarely, on species of Parmotrema, Punctelia, etc.).

Usually this species is found in its asexual form (anamorph) but it can also present some more or less aborted apothecia in addition to the pycnidia (homomorph), the sexual form (teleomorph) is very rare.

Be careful of very similar species that are sometimes confused:

_ Abrothallus parmeliarum on Parmelia saxatilis.

_ Abrothallus parmotrematis on Parmotrema sp. usually in its sexual form with larger spores.

_ Abrothallus prodiens on Hypogymnia physodes

Abrothallus microspermus Tul.