Hello,
On the 11th of May 2023 I found in Hengelhoef, Houthalen (Belgium), in forest, this Peziza:
Length about 5-6 cm, width 3-4 cm, hymenium according to Standard Soil Color Charts 7.5 YR 4/6 brown and 5/6 bright brown; exterior much paler and soon appearing grey-white; no juice present when injured; growing near beech and oak, on the soil or on small twigs; spores with small warts, < 1 µm high, not apiculate, in water with 2 large oil drops; spores in water: (16.0-) 16.8-18.4 (-19.2) x (8.2-) 8.9-10.3 (-11.0) µm, Q= (1.6-) 1.7-1.9 (-2.0), spores in coton blue: (15.5-) 16.4-18.2 (-19.1) x (8.3-) 8.8-9.8 (-10.3) µm, Q= (1.7-) 1.8-2.0 (-2.1); asci Melzer +, paraphyses simple, with small club-shaped thickening on top, with colourless content, not moniliform; excipulum: layered with different types of layers (hyphae, round cells, some angular cells.
Seems to be Peziza alvernensis, except the presence of 2 oil drops in all spores; an other possibility is Peziza domiciliana but I haven't any idea about the excipulum of this Peziza. The spores are too small for Peziza emileia and too big fot Peziza domiciliana.
Who can help?
Luc Lenaerts