Nemania gwyneddii

              

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JF01082

JF01082

JF01082

JF01082

Nemania gwyneddii (Whalley, Edwards & Francis) Pouzar.

Stromata superficial, ellipsoid-elongate, 11-25 mm long x 3-4 mm broad x 0.6 mm thick, weakly carbonaceous; surface blackish brown to dull black, with inconspicuous perithecial mounds; interperithecial tissue soft, dark grey, inconspicuous; margin narrowly effused, black.

Perithecia subglobose, 0.5-0.6 mm diam.

Ostioles minutely papillate, black.

Asci fragmentary, not measured, short-stipitate according to the type description, with apical apparatus amyloid, urn-shaped to cylindrical, 5-7 m high x 3-4 m broad.

Ascospores 20-26 (-29) x 7-11 m, pale brown, ellipsoid-inequilateral with broadly rounded ends, sometimes with one end pinched, with a short, fairly conspicuous germ slit 3.5-4 m long on the more convex side.

Specimen examined: FRANCE: Arige (09): Rimont, Saurine, 28 Apr. 2001, JF-01082, on wood of Fraxinus excelsior.

Notes: This specimen was identified to N. gwyneddii relying on the particularly large dimensions of apical apparatus and ascospores. Nemania gwyneddii is a very rarely recorded species, previously only known from the type collection in Wales, U. K., (Whalley et al., 1983). Unlike this material which was said to be "somewhat immature and scanty" by Ju and Rogers (2002), our collection consists of two overmature and depauperate stromata in which only three perithecia were found to be ascigerous.This could explain the apparent discrepancy between ascospore shape in both collections, more slender in the type collection than in ours.

Nemania gwyneddii is macroscopically much like N. serpens, but is characterized by a massive amyloid apical apparatus and large pale brown ascospores averaging 25 m long with a very short but fairly conspicuous germ slit on the more convex side. Petrini and Mller (1986), when examining the type collection, reported this germ slit as spore-length, without mentioning its situation on the more convex side.

The type material of N. gwyneddii was collected on wood of Fraxinus and on unidentified wood (Whalley et al., 1983). Our collection is likewise on Fraxinus, which could indicate a host-preference.