Carnivorous Hammerhead Flatworms Are Invading France

It’s no hammerhead shark, but the hammerhead flatworm has become a real menace in France. Or at least a menace to earthworms, as Earther reports.

Believed to be an invasive species from Asia, the hammerhead flatworm was only recently recorded in France, as is documented in a new study (titled "Giant worms chez moi!") published in the journal PeerJ. However, based on reports, photographs, and videos sent in by citizens across the country, scientists determined the pests have gone undetected for nearly 20 years. This came as a shock, especially because the worms can measure more than a foot in length.

In recent years, three species of the carnivorous worm have quietly taken over French gardens and have even been spotted in metropolitan areas. Some species immobolize their prey with tetrodotoxin, the same powerful neurotoxin that makes pufferfish so poisonous. The worms secrete digestive enzymes, allowing them to dissolve earthworms and slugs their size.

Jean-Lou Justine, co-author of the study, says their eating habits are a concern. "Earthworms are a major component of the soil biomass and a very important element in the ecology of soils," Justine tells Earther. "Any predator which can diminish the populations of earthworms is thus a threat to soil ecology."

Archie Murchie, an entomologist who was not involved in the study, told The Washington Post that the worms will continue to spread in step with global trade. The worms were also seen in overseas French territories, including one worm with a blue-green hue that is probably a newly detected species, Murchie tells the newspaper.

[h/t Earther]

This Wall Chart Shows Almost 130 Species of Shark—All Drawn to Scale

Pop Chart Lab
Pop Chart Lab

Shark Week may be over, but who says you can’t celebrate sharp-toothed predators year-round? Pop Chart Lab has released a new wall print featuring nearly 130 species of selachimorpha, a taxonomic superorder of fish that includes all sharks.

The shark chart
Pop Chart Lab

Called “The Spectacular Survey of Sharks,” the chart lists each shark by its family classification, order, and superorder. An evolutionary timeline is also included in the top corner to provide some context for how many millions of years old some of these creatures are. The sharks are drawn to scale, from the large but friendly whale shark down to the little ninja lanternsharka species that lives in the deep ocean, glows in the dark, and wasn’t discovered until 2015.

You’ll find the popular great white, of course, as well as rare and elusive species like the megamouth, which has been spotted fewer than 100 times. This is just a sampling, though. According to World Atlas, there are more than 440 known species of shark—plus some that probably haven't been discovered yet.

The wall chart, priced at $29 for an 18” x 24” print, can be pre-ordered on Pop Chart Lab’s website. Shipping begins on August 27.

Can You Really Suck the Poison Out of a Snakebite?

iStock
iStock

Should you find yourself in a snake-infested area and unlucky enough to get bitten, what’s the best course of action? You might have been taught the old cowboy trick of applying a tourniquet and using a blade to cut the bite wound in order to suck out the poison. It certainly looks dramatic, but does it really work? According to the World Health Organization, approximately 5.4 million people are bitten by snakes each year worldwide, about 81,000 to 138,000 of which are fatal. That’s a lot of deaths that could have been prevented if the remedy were really that simple.

Unfortunately the "cut and suck" method was discredited a few decades ago, when research proved it to be counterproductive. Venom spreads through the victim’s system so quickly, there’s no hope of sucking out a sufficient volume to make any difference. Cutting and sucking the wound only serves to increase the risk of infection and can cause further tissue damage. A tourniquet is also dangerous, as it cuts off the blood flow and leaves the venom concentrated in one area of the body. In worst-case scenarios, it could cost someone a limb.

Nowadays, it's recommended not to touch the wound and seek immediate medical assistance, while trying to remain calm (easier said than done). The Mayo Clinic suggests that the victim remove any tight clothing in the event they start to swell, and to avoid any caffeine or alcohol, which can increase your heart rate, and don't take any drugs or pain relievers. It's also smart to remember what the snake looks like so you can describe it once you receive the proper medical attention.

Venomous species tend to have cat-like elliptical pupils, while non-venomous snakes have round pupils. Another clue is the shape of the bite wound. Venomous snakes generally leave two deep puncture wounds, whereas non-venomous varieties tend to leave a horseshoe-shaped ring of shallow puncture marks. To be on the safe side, do a little research before you go out into the wilderness to see if there are any snake species you should be particularly cautious of in the area.

It’s also worth noting that up to 25 percent of bites from venomous snakes are actually "dry" bites, meaning they contain no venom at all. This is because snakes can control how much venom they release with each bite, so if you look too big to eat, they may well decide not to waste their precious load on you and save it for their next meal instead.

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