Summary:
Trichobolus zukalii produces a minute fruitbody on deer dung that consists of an ascus containing 5800-7200 spores per ascus, more than in any other ascomycete. It is barely visible to the naked eye but under low magnification reveals an ovoid structure that is white in the upper one third and yellowish to olive-brown in the lower part, with setae extending in all directions. Spore liberation is by an irregular tear at the top of the ascus.

Microscopic:
fruitbody composed of a 4-cell to 8-cell thick layer of hyphae enclosing a single ovoid to pyriform [pear-shaped] ascus, 310-525 x 275-440 microns, containing about 5800 to 7200 spores per ascus; each spore 9.7-10.5 x 7.0-7.6 microns, oval, smooth, thin-walled, in some media containing a prominent gaseous vacuole (deBary bubble) 4.5 x 3 microns, cytoplasm granular; ascus wall "relatively thick (4.6-5.5 microns) but gradually becomes thinner (2.4-3.0 microns) at the pear-shaped ascus apex", the wall has three layers that can be differentially stained with 2% aqueous congo red; paraphyses more prominent when young, a single layer of narrow (2.5 microns wide) filaments extending from the base of the ascus to its apex, pressing close together in a mucilaginous matrix completely enclosing the ascus; setae about 15-20 per fruitbody, 90-600 microns long (average 325 microns), up to 12-15 microns wide at base, the setae containing 3-5, occasionally 10 or more, thin septa, the thick walls becoming thinner as they extend into the basal cell, (Kimbrough(3))

Notes:
Trichobolus zukalii is found in BC, AB, MB, ON, MA, and NY, (Kimbrough(4)), and Denmark and Sweden, (Hansen).

Synonyms and Alternate Names:
Coniophora corrugis Burt
Corticium corruge (Burt) D.P. Rogers & H.S. Jacks.
Thelebolus zukalii Heimerl