Ultrastructural evidence for the placement of the truffle Barssia in the Helvellaceae (Pezizales)

Abstract

The truffle genus Barssia has been included in three different families of Tuberales and one of the Pezizales. Light and electron microscopic examinations were made in order to resolve the proper systematic position of Barssia and its relationship to other epigeous and hypogeous Pezizales. Smooth, tetranucleate ascospores with a large vacuole and structures in the septal pores of asci, ascogenous hyphae, and vegetative cells confirmed that Barssia oregonensis belongs in the Helvellaceae. Its relationship to species of Helvella, is discussed.

Key Words:

• Ascomycetes
• cup fungi
• discomycetes
• septal structures
• phylogeny
• ultrastructure