Lachnum crataegi

A species associated with Crataegus, though not exclusive to it, white, cup-shaped with a well-defined stipe and a disc diameter of 1-3 mm.

Marginal hairs cylindrical, hyaline, septate, 85-105 µm long and 3.3-5 µm wide, covered with fine hyaline crystals giving a roughened appearance.

Medullary excipulum of textura intricata, formed by hyaline hyphae densely interwoven, 4-7 µm wide, with short septa and inflations up to 9 µm.

Ectal excipulum of textura globulosa-angularis, hyaline, slightly thick-walled, 20-35 µm long.

Asci cylindrical, 8-spored, with biseriate to irregular spore arrangement, 55-65 µm long and 4-5.5 µm wide, lacking croziers, with an amyloid apical apparatus in Melzer's reagent.

Paraphyses lanceolate, up to 5 µm wide, projecting 3-20 µm above the asci, without vacuolar content.

Ascospores cylindrical to slightly fusiform, smooth, hyaline, thin-walled, homogeneous inside, without oil content.

Very similar to its congener, Lachnum fasciculare, the latter having shorter asci (barely over 50 µm) and croziers at their base.

Herbarium material available: JTP2492/25 and JTP2688/25.