Acanthophysis-like structures from wood submerged in freshwater streams in the tropics

Acanthophysis-like structures which commonly occur on submerged wood in the tropics are described and illustrated at the light microscope level. These are produced on fibre-like or rope-like strands and produce numerous detachable spinulose cells at their ends. These cells lack contents, do not germinate, and do not appear to be dispersal propagules. The acanthophysis-like structures may function as rhizomorphs enabling the fungus to colonize adjacent woody tissue, or serve to uptake oxygen from the water and these possibilities are discussed.