Woman stumped by 'super weird' growth at her Sydney home

The woman said the strange and 'hairy' substance is growing from, or has attached itself, to her doormat.

A baffled homeowner was scratching her head this week after making an unusual discovery in her garage — so strange, in fact, it's even left some experts stumped.

The Sydney woman, who wished to remain anonymous, said she had "zero idea" what the "super weird" growth is on her doormat, so she pleaded with her community to find out.

The woman told Yahoo she made the furry discovery on Wednesday and hadn't noticed it until now. "There was a black pattern on the mat, so [it was] probably not obvious until it got that big," she said.

Posting photos on her local community Facebook page she admitted she thought it was "a ball of dog's fur" at first, but then she suggested it was a rodent thanks to the long, black hairy appearance.

"It's growing from, or attached itself, to my doormat," she said alongside the pictures. "Anyone know what on earth it is? Super weird and definitely not touching it," she added.

Black hairy mould on doormat.
A Sydney woman was shocked by the hairy growth on her doormat. Source: Facebook

The unusual growth amused many who compared the hair to "gremlins" or "something out of Stranger Things" — a reference to the hit supernatural TV show.

Jokes aside though, many concluded it was some kind of household mould, however unusual it might seem. One person suggested it could be a hairy fungus known as Alternaria, a major plant pathogen that can often grow indoors.

Experts weigh in on mystery growth

Yahoo sought the expertise of Dr Cécile Gueidan, Senior Research Scientist at the Australian National Herbarium in Canberra. Although "not a mould specialist," and based only on the photos, she said she's "not convinced it is an Alternaria".

"It could still be fungal, but a sample would be needed for microscopy," she added.

Anyone know what on earth it is? Super weird and definitely not touching it.Sydney resident

Professor David Catcheside from Flinders University agreed "a photograph is unreliable and laboratory examination is usually needed" to accurately identify any type of fungus or mould.

"However, the mould appears to be a saprophyte digesting the mat, doing its normal job of recycling organic materials," he said.

Saprophyte is an organism, usually a fungus or bacterium, that lives on and feeds off dead or decaying organic matter.

Mould warning: 'Can cause disease'

Without knowing exactly what it is, there's still a warning to be issued about most forms of mould, Professor Catcheside said.

"Moulds produce spores which may be allergenic and in some instances, particularly for individuals who are immunocompromised, can cause disease," he explained. "So it would be wise to dispose of the mat and clean the area with a disinfectant.

"The mould would require moisture to grow so it would be wise to replace the mat with one that is rot resistant, such as one not composed of natural fibre."

The homeowner told Yahoo they "assumed it was mould" and have since thrown out the doormat.

While it remains somewhat of a mystery, Yahoo has reached out to several other mycology [fungi] experts and will update the story if this wild growth is positively identified.

Do you have a story tip? Email: newsroomau@yahoonews.com.

You can also follow us on Facebook, Instagram, TikTok and Twitter and download the Yahoo News app from the App Store or Google Play.