Spirodecospora (Xylariaceae)

a new genus for Western Europe, characterised by spores with spiralling ornamentation

Abstract

Spirodecospora is a xylariaceous genus occurring on bamboos, characterised by minute, discrete, deeply immersed, nonstromatic ascomata yielding fairly large, distinctive ascospores with a pigmented, spirally ornamented wall. Its known distribution so far is temperate (Japan) to tropical (Hong Kong). A pyrenomycete collected on Arundinaria sticks in Devon (UK) proved to match this morphological definition of Spirodecospora in all respects. A detailed morphological description of this collection is provided. An ITS sequence obtained from this material supported this view by showing 99.8% similarity to S. melnikii, a species known from Japan and Far East Russia on Sasa. Our results therefore considerably expand the known geographic range of Spirodecospora.

This collection is herein assigned to S. melnikii, which may be a synonym of the type of Spirodecospora, S. bambusicola; DNA data from the type specimen of S. bambusicola is not yet available. To explain the unexpected presence of S. melnikii in Western Europe, its endophytic origin from live bamboo material imported from Asia is considered.