Snorkeller Mat Rogerson was gathering undersea rubbish when he picked up a deadly passenger.
Posting in the Snorkeling Western Australia Facebook group, Rogerson said he had been snorkeling at North Beach in Perth for about an hour before returning home with the gathered trash.
While watering the garden, Rogerson said he "suddenly" noticed a blue ringed octopus crawling out of his snorkeling gear.
"Didn't feel a bite, but now read the bite is painless," he said
Rogerson carefully took the octopus back to a groyne with seaweed and set it free.
"Either came out of black snorkel, or blue rubber dog ball, with hole in it, as other junk had no hiding places," he wrote.
"I'll be far more careful what I tuck into my wetsuit in (the) future."
The blue-ringed octopus is one of Australia's deadliest sea creatures, with a powerful neurotoxin that can kill in minutes.
Other members of the snorkeling group marvelled at Rogerson's lucky escape - suggesting he'd earned it with his clean-up efforts.
"Karma. You did good. Little bluey let you have a pass," one member wrote.
A grotesque black fish, which has sharp teeth resembling shards of glass has washed up on a beach in California.
The creature, believed to be a female Pacific footballfish, was found on the shoreline of Crystal Cove State Park in Orange County.
The fish themselves are "very rare", and it's unknown how or why it ended up on the shore, according to state park officials.
The species is believed to be one of more than 200 species of anglerfish world wide.
The jet-black fish possess a long stalk on the head with a bioluminescent tip, which is used to lure and entice prey in pitch black water as deep as 3000 feet.
Their terrifying teeth are transparent in the water and their large mouth is capable of sucking up and swallowing prey the size of their own body.
Researchers have spotted a rare Dumbo Octopus during a live broadcast expedition in Papahānaumokuākea Marine National Monument, in the Northwestern Hawaiian Islands.
Only 17 species of the octopus have been discovered, as they usually live at extreme depths, according to the UK Natural History Museum.
The researchers can be heard on the broadcast marvelling at the sea creature, saying the light shining on the mollusc makes it look "spooky" as it floats through the water.
Researchers say they're still "stumped" by an object they plucked from a rocky outcrop about 3.3km below the surface of the ocean in the Gulf of Alaska.
The US-based National Oceanic and Atmospheric Administration's expedition made headlines around the world when images of a "golden orb" captured by a remote undersea vehicle went viral in late August.
The vehicle retrieved the 10cm object as a sample, which scientists were unable to originally identify.
Initial thoughts ranging from a dead sponge attachment, to coral, to an egg casing.
Now aboard ship, the researchers aren't much closer to figuring out what it is - only that it is biological.
"Isn't the deep sea so delightfully strange?" expedition coordinator Sam Candio said.
"While somewhat humbling to be stumped by this finding, it serves as a reminder of how little we know about our own planet and how much is left to learn and appreciate about our ocean."
He said more would likely be discovered about the mysterious object in a lab setting.
A French angelfish that was unable to right itself in a US zoo has undergone scans more often used for 318kg grizzly bears.
The seven-inch fish was suffering from inflamed intestines, causing a buildup of internal gas, causing it to swim off balance.
The angelfish needed a CT scan to diagnose its gassy condition.
Denver Zoo veterinarians had to sedate the fish and prop it up on a sponge while pouring water over the animal to keep it alive during the scan.
Denver Zoo spokesperson Jake Kubie said the fish is doing much better after treatment.
"It was treated with antibiotics," he said.
"It's doing much better and swimming normally."
The fish's intestines can be seen in this image of the scan.
CSIRO scientists on board a research vessel have sighted an extremely rare narrowbody handfish, off the coast of Tasmania.
The fish was caught on camera at a depth of 292 metres using a deep-tow camera system. It's the first time the fish has been seen since 1996.
The Australian National Fish Collection has only two specimens of the very rare fish on record since it was first discovered in 1986.
The narrowbody handfish is a demersal species, or groundfish, which is only found off southeast Australia.
"I was really hoping to find a deepwater handfish on our cameras during this voyage. To find one so early on in the trip was incredible," research technician Carlie Devine said.
"We suspect it's a narrowbody handfish. But this handfish is much bigger than the two we have on record and is about 100 kilometres away from its current known location. We can't be 100 per cent sure which handfish species it is. This is as close as we can get without seeing others or collecting a sample fish."
Researchers have learnt more about a bizarre deep-sea creature known as an "Antarctic strawberry feather star" (Promachocrinus fragarius).
Writing in the journal Invertebrate Systematics, researchers Emily McLaughlin, Nerida Wilson and Greg Rouse found four similar types of "crinoids" - creatures that are similar to sea feathers.
This particular crinoid is named the strawberry after its bulbous head and features more than 20 tentacles.
A new species of sea star has been discovered, the deepest yet found in Australian waters.
Museums Victoria first encountered the creature, poraniomorpha tartarus, in a 2017 expedition that ventured 4000 metres below the ocean's surface off Australia's eastern coast.
But it's only recently been scientifically described in the Memoirs of Museums Victoria.
US expert Dr Christopher Mah told Cosmos it was the first time this genus of sea star had been recorded not just in Australian waters, but in the Southern Hemisphere.
The sea star was found at a depth of 3850 metres.
An unusual ancient marine reptile may have gulped down tons of shrimplike prey using a feeding technique similar to one used by some modern whales.
The reptile, named Hupehsuchus nanchangensis, lived in Earth's oceans between 247 million and 249 million years ago, during the early Triassic Period.
Fossils of the reptile were first found in China in 1972. But researchers have struggled to understand the animal's feeding behavior and lifestyle because none of the skulls were well preserved.
Two newly discovered fossils unearthed from China's Jialingjiang Formation in Hubei province include the nearly complete skeleton of one reptile and a large portion — from head to collarbone — of another.
Hupehsuchus and minke whale skulls compared.
The discoveries enabled researchers to take a closer look at Hupehsuchus nanchangensis and determine that the reptile had a toothless snout and a small, narrow skull. Its lower jaw was loosely connected to the rest of the skull, which means the creature could expand its mouth — similar to how modern whales eat by filter feeding.
A study detailing the findings was published Tuesday in the journal BMC Ecology and Evolution.
"We were amazed to discover these adaptations in such an early marine reptile," said lead study author Zichen Fang at the Wuhan Center of China Geological Survey, in a statement.
"The hupehsuchians were a unique group in China, close relatives of the ichthyosaurs, and known for 50 years, but their mode of life was not fully understood."
Whales evolved about 15 million years after dinosaurs went extinct at the end of the Cretaceous Period 66 million years ago. And it took about 17 million years for whales to evolve their filter-feeding adaptations, according to the study.
But this same technique was quickly adapted, within about five million years, by marine reptiles that lived much earlier than whales.