Other specimen examined: Japan, on Pyrus pyrifolia, coll. H. Ishii Nashi-10 (ICMP 18686).

Colonies grown from single conidia on Difco PDA 30–35 mm diam after 10 d. Aerial mycelium sparse, cottony, white, surface of agar uniformly pale orange (7A5) towards centre, more or less colourless towards edge, conidia not associated with well differentiated acervuli and no masses of conidial ooze. In reverse pale orange towards centre. Conidiogenous cells arising haphazardly from dense, tangled hyphae across agar surface, short-cylindric with a poorly differentiated conidiogenous locus. Conidia often germinating soon after release, sometimes forming appressoria, so forming a thin, compact, layer of germinated, septate conidia, germ tubes, and appressoria across the central part of the colony surface. Conidia (12–)14–15(–16.5) × (5–)6– 6.5(–7.5) μm (av. 14.5 × 6.1 μm, n = 53), cylindric with broadly rounded ends. Appressoria 6–10 μm diam, subglobose or with a few broad lobes.

Geographic distribution and host range: known from only two collections, one from Pyrus pyrifolia from Japan, the other from Persea americana from Israel.

Genetic identification: ITS sequences are insufficient to separate C. aenigma from C. alienum and some C. siamense isolates. These taxa are best distinguished using TUB2 or GS. Notes: Although the biology of this species is more or less unknown, it has been found in two widely separate regions and is, therefore, likely to be found to be geographically widespread in the future. Genetically distinct within the Musae clade, this species has a distinctive appearance in culture with sparse, pale aerial mycelium and lacking differentiated acervuli.

Holotype: Israel, on Persea americana, coll. S. Freeman Avo-37-4B, PDD 102233; ex-holotype culture ICMP 18608.