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Thecotheus pelletieri

32-spored ascus (count them!)

The ascospores are shot out through a 'lid' at the apex (below) of the ascus called an operculum.  In this photomicrograph you can see the line of breakage of the operculum near the tip (arrow, see close-up below).  This line is weaker than the rest of the ascus wall.  At maturity of the spores the osmotic pressure inside the ascus builds up and and finally it causes the line of weakness at the operculum to break and the contents are squirted out.  The ascospores are not shot off a great distance (10-60 cm or so) but this is sufficient to get them into the air for dispersal.  Or, as for coprophilous fungi, far enough from the dung to stick to adjacent plants and be eaten later by foraging herbivores.

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