Hysterobrevium smilacis

The fruit body is black, hard, generally 0.5-2 millimetres in length, much narrower than long, not taller than wide and with a fissure running along the length of the fruit body. The fruit bodies usually appear in large groups. Technically this type of fruit body is called a hysterothecium and hysterothecial fungi are ascomycetes. Hysterothecial fungi are fairly common but easily overlooked. Often you find them on hard, weathered wood in exposed habitats (e.g. on old wooden fence-posts, power poles or paling fences).

Hysterobrevium smilacis is a cosmopolitan species.

Look-alikes

There are about a dozen genera in the families Hysteriaceae and Gloniaceae with such hysterothecia and identification of genera relies heavily on spore features. Microscopically, Hysterobrevium smilacis has some similarities to Gloniopsis praelonga (see comments at http://canberra.naturemapr.org/Community/Species/22550).

Other hysterothecial genera on Canberra Nature Map

Gloniopsis

 Hysterobrevium

Oedohysterium