Two new species and a new record of Astrocystis from Southwestern China

Abstract

In this study, three species of Astrocystis were collected from bamboo culms in Guizhou and Yunnan Provinces in China. Morphological characteristics and phylogenetic analyses (based on ITS, rpb2, βtubulin and α-actin gene regions) supported the proposal of two new species viz., Astrocystis pseudomirabilis sp. nov. and A. tessellati sp. nov. and a new record of A. sublimbata from China. Astrocystis pseudomirabilis can be distinguished from A. mirabilis by its larger stromata (0.64–0.83 × 0.38–0.52 mm vs. 0.4–0.6 × 0.2–0.5 mm) and larger ascospores (11–14 × 6–8 μm vs. 10–12 × 4.5–6 μm). Astrocystis tessellati differs from A. multiloculata by its smaller ascospores (16.2–19.2 × 7.2–9 μm vs. 19–25 × 7–11 μm). Astrocystis pseudomirabilis and A. tessellati form two distinct clades within Astrocystis.