ostiole

Borrowed from Latin ostiolum.

ostiole (plural ostioles)

1. (mycology) A small hole or opening through which certain fungi release their mature spores.
   • 2010, Helen Gwynne-Vaughan, Fungi: Ascomycetes, Ustilaginales, Uredinales, page 54:

     The Erysiphacae may possibly have given rise to the Laboulbeniales, the only other group in which a single daughter cell of the oogonium is responsible for the asci, and perhaps to the lower Pyrenomycetes also; these, like the Erysiphaceae, have regularly arranged asci, and in Chaetomium fimete the perithecium is without an ostiole.

2. (botany) A similar hole or opening in plants, such as the opening of the involuted fig inflorescence through which fig wasps enter to pollinate and breed.

• ostiolar
• ostiolate

• Osloite, oolites, oölites, stoolie, toolies