Australia has more than 100 different species of praying mantises, most of which are only found here.

But how would you know if you saw one that wasn’t native?

That requires the expertise of an entomologist — specialists who are able to identify species of insects.

Australian Museum’s mantis expert, Graham Milledge, does just that, and he recently received an express-posted package containing a mantis thought to be invasive to Australia. 

Dr Milledge said the adult female specimen arrived in good condition and appears to be the introduced species Miomantis caffra.

“As with a lot of invertebrates, you really need an adult male to identify it,” he said. “Also, I don’t have any other specimens to compare it with.” 

He says he is not aware of any other introductions of a praying mantis in Australia. 

But this particular specimen had taken a circuitous route via an unlikely source. The mantis was ‘discovered’ on the photo-sharing platform Flickr where it had been posted by amateur photographer Adam Edmonds in 2009. 

Mr Edmonds, 44, had been visiting his mother in Grovedale, Geelong one weekend when he spotted a vibrant green-coloured mantis sitting on his mother’s doormat.

“So that one actually found me,” he said.

The image remained on Flickr unnoticed for five years, until late 2014, when Mr Edmonds spotted another mantis balancing gracefully on his mother’s fence.

“I posted [the new photograph] on Flickr, but this time someone commented saying it was a Miomantis caffra,” Mr Edmonds said. “Then someone else said that we don’t get those in Australia, so it must be another species.”

Then, one of the site’s users contacted an expert who wrote on Flickr that the sighting did indeed look like the Miomantis caffra. 

Encouraged by the comments, Mr Edmonds posted the photograph on BowerBird – a photo-sharing site monitored by scientists — where Melbourne Museum’s senior curator of entomology, Ken Walker, saw it. He, in turn, contacted Dr Milledge.

Dr Milledge confirmed that it looked like the South African Miomantis caffra, recorded as invasive to New Zealand since 1978 and, more recently, to Norfolk Island.

Dr Walker, meanwhile, notified the Australian Quarantine Inspection Services, which requested the specimen be “collected, preserved and identified by the relevant expert”. He then contacted Mr Edmonds again to ask if he could find another specimen and bring it to the museum.

“I managed to get one the weekend after that and I walked it into Melbourne Museum during my lunch break to drop it off,” said Mr Edmonds, who works nearby, as an instrument technician at Melbourne’s St Vincent’s Hospital.

“It was quite a bit of a stir to me when I found out what it was. Mum was pretty interested in it too,” he said.

Dr Milledge said the species was highly unlikely to become a pest like some other invasive species such as the cane toad.

“The only possible problem is that it may displace native species. But I would think that is fairly unlikely to,” he added. 

“That’s the great thing about the internet. There’s much greater chance of people seeing it and it being identified.”

The mantis likely arrived in Australia via ship as either an adult or egg case, possibly attached to the side of a shipping container heading to Geelong, Dr Walker speculated.

As a consequence, he put out a call on BowerBird asking Victorian users to photograph any mantis they saw in their travels over the summer months.

Last week, he headed to Brighton, Melbourne after being alerted to Facebook images suggesting the Miomantis caffra species had also been spotted there.

“I secured the egg case, which is characteristic of Miomantis, but despite an hour-long search, we did not find an adult,” he said. “It just shows the importance of social media now to biosecurity and biodiversity.”

Dr Walker will attempt to rear the specimens from the egg case at the Melbourne Museum, while remaining on the look out through social media platforms for more.