Ascotricha Xylina: Its Occurrence, Morphology, and Typification

ABSTRACT

The isolation of Ascotricha xylina from sunflower (Helianthus annuus) oilseed grown in the U.S. is the first record of this fungus from sunflower seed and from the Western hemisphere. Examination of specimens of A. xylina from world herbaria confirmed the determination as A. xylina, and led to the discovery of the holotype that was lost for 33 years and the recognition of an isotype. The sizes of ascospores and widths of perithecial hairs from these specimens showed greater variation than described by Ames. Undescribed conidiogenous areas on perithecial hair apices were observed in culture. Centrum tissues appeared similar to other Ascotricha species, with broad, septate paraphyses interspersed among asci with non-amyloid apices.

Key Words:

• Ascotricha xylina
• holotype
• isotype
• new record