Bonjour,
Trois ascocarpes, jaune vif, jusqu'à 0,7 mm de diamètre, étaient sur bois mort. Les spores sont courbées et cloisonnées. Je l'ai cherché chez Fungi of Switzerland, Ellis & Ellis et Peter Thompson, mais sans succès.

These 3 small bright yellow discos were on dead wood (in mostly oak and birch woods but in the vicinity of alder and sycamore). Possibly on old pyrenomycete, but not sure.  Ascocarp diameter up to 0.7 mm. Sessile. Hairy. Spores mostly curved, up to 22 x 5 um with at least 3 septa. Asci blueing in Meltzer's. e.g. 75 x 7 um. Paraphyses thread-like but irregular. Hairs 5 um wide filled with small refractive droplets.
I am unable to identify this lovely little disco - but I'm sure it must be well-described somewhere.
Cordialement,
Steve