While seasonal change can be marked by the cooler weather and browning leaves, there is one other sure way of knowing when autumn is around the corner – spider season.

Dozens of social media users have reported seeing eight-legged creepy crawlies in their homes in recent weeks, with some posting pictures of the arachnid invaders.

Recruitment consultant Martin, 41, from Redhill, Surrey – who did not want to give his full name – tweeted a picture of a spider he found in his home on Sunday night next to a 1p coin for comparison.

He said: “I was catching up on A League Of Their Own after my wife had gone to bed, I saw this thing come out from under the TV cabinet and scuttle past our sleeping greyhound.

“Luckily the dog stayed asleep and the wife and kids were asleep. I’m not scared of spiders but you wouldn’t want to meet this thing in a dark alley.

“It was in the lounge and probably three times the size of a very large house spider.”

Professor Adam Hart, an entomologist at the University of Gloucestershire, said a 2018 study showed 82% of spiders spotted indoors at this time of year are males.

“They get quite wandery, going around looking for females, which they can be quite determined about,” he said.

“Houses are just another habitat to wander around, the females are quite sedentary and stay in places like sheds and underneath windowsills.”

Some people have commented on the monstrous sizes of these harmless house spiders, but Prof Hart said arachnids belonging to the species Tegenaria domestica and Eratigena atrica – also known as the giant house spider – are “generally quite large”.

According to The Wildlife Trusts, the giant house spider – identified by its dark hairy body and long legs – typically has a leg span of up to 7.5cm and can run up to half a metre per second.

Keeping your house tidy and keeping clothes off the floor may reduce places for them to hide, but it's very difficult to keep them out

“If we are not used to seeing them around, they do appear quite big,” Prof Hart said.

“There are a couple of male spiders in those species that are quite formidable-looking, but the reality is they’re quite harmless.”

The spider season will not last long, Prof Hart said, and arachnophobia sufferers will be relieved to learn it ends around the start of October.

While an old wives’ tale encourages people to place conkers at windowsills to keep spiders at bay, the best thing a person can do is to keep windows and doors shut.

As more people are spending their evenings indoors, Prof Hart said 7.35pm was the peak time of when spiders are spotted lurking around the house.

He continued: “There’s nearly always a way to get in the house, they can also come in through things like towels that are left outside.

“Keeping your house tidy and keeping clothes off the floor may reduce places for them to hide, but it’s very difficult to keep them out.”