Otidea microspora

A taxon considered somewhat critical in monographs of the genus though currently treated as distinct, very close to Otidea alutacea but possessing considerably smaller spores; with ear-shaped apothecia up to 4.5 cm in diameter and 7 cm tall, yellowish-brown.

Medullary excipulum of textura intricata, with interwoven hyaline filamentous hyphae 4–10 µm wide.

Ectal excipulum of textura globulosa-angularis, with subspherical to vesiculose, hyaline, moderately thick-walled cells 20–45 µm long by 16–35 µm wide.

Asci cylindrical, 8-spored, pleurorhynchous, measuring 130–170 µm long by 9–11.5 µm wide, uniseriate, inamyloid in Melzer's reagent.

Paraphyses filiform, septate, branched at the base, with strongly curved hooked or crozier-like apices, 2–3 µm wide with apical swellings 3–4.5 µm wide, containing abundant refractive yellowish granules inside.

Ascospores ellipsoidal, smooth, hyaline, moderately thick-walled, measuring 9–10.5 µm long by 5–6 µm wide, with two large oil guttules inside.

Very close to Otidea alutacea, which has spores measuring 13.5–17.5 µm long by 6.5–8 µm wide, dimensions well above those of the species described here.