Umbagong Fungi Project: Tiny: on a fallen dead tree trunk. Found at the eastern end of the park. The individual lumps (no more than a millimetre or so in diameter) are separated from each other. We've also found these fungi on logs close to the sewer pipe (Macgregor side of the creek).
Heino's comments: “ lumps are separated ... unlikely to be cobblestone fungi. I think each lump is too small to be a group of fused fruitbodies.
One possibility that each lump is a single fruitbody that resembles a single cobblestone, but in Annulohypoxylon you expect to see fused cobblestones (albeit with the occasional one perhaps a little separated), not all clearly separated cobblestones. Furthermore, each of the fused cobblestones has to have a pimple-like protrusion at the apex. If you see it again it would be worth checking if it's powdery. You could rub a finger or a white tissue over a few of these lumps and see if you pick up a dark powder. If so, one possibility is that you are picking up the asexual spores of some fungus. I often see such powder-producing, dark brown to blackish lumps, in abundance, on dead but still firm wood. I haven't tried to identify the fungus.”
Response: When rubbing the fungi, black powder came off but the lumps stayed firm and did not disintegrate.