The woman who posted the images told Yahoo News she had done so on behalf of a friend who recently lifted the wet floorboards, only to discover the strange mass. Stunned by the find, the woman sought advice from a local Facebook group, asking fungus enthusiasts if they had "any ideas what this is".
The incredible photos show the entirety of the floor covered in a distinctive black web-like pattern — which some compared to the upside down in the popular science fiction horror show Stranger Things.
The suggestions came in thick and fast as to what it could be, but no one could agree. "Mycelium", "slime mould" and "tree roots of some sort," some suggested.
The sight was enough to make some Aussies say "nooope". "I'm genuinely terrified," another admitted. Even some experts were stumped by the "odd" discovery.
"It's a new one to me too. Certainly doesn't look like traditional mould," an expert from the state herbarium in Brisbane told Yahoo News.
"The only thing I know that looks remotely like that are the rhizomorphs of Armillaria (honey fungi), but that doesn't make a lot of sense," he added. The term Rhizomorph, is known to be a threadlike or cordlike structure in fungi (Kingdom Fungi) composed of parallel hyphae, branched tubular filaments that comprise the body of a typical fungus.
Experts weigh in on 'odd' discovery
Elizabeth Aitken, Professor in Plant Pathology at the University of Queensland, agreed "it certainly looks like the rhizomorphs of a wood rot fungus".
"Whether this is the dry rot fungus or something else they would need to take samples or ask a timber specialist," she told Yahoo News.
Dr Heike Neumeister-Kemp, Principal Mycologist at Managing Director of Mycolab said, "this is definitely, fungal mycelium most likely from a basidiomycetes" — a type of fungi which are "actually not dangerous" and will form a fruiting body (toadstool or mushroom).
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