How scary is the "Black Widow" seized by customs?

Recently, the Xiamen Customs in Fujian intercepted a live smuggled spider called "Black Widow", which attracted widespread attention from the media.

As a well-known super poisonous creature, the "Black Widow" is more than 10 times more poisonous than a rattlesnake. If it invades our country, it will have extremely serious consequences.

This is not an exaggeration. Although the real "Black Widow" is not as big as a human and does not hunt people in groups as in movies and TV shows, it is still terrifying with its extremely strong toxicity, high reproductive capacity, and high mortality rate caused by its bites.

Ruthless by nature

"Black widow" is a general term for all members of the genus Theridiidae, also known as hourglass spiders and deadly red-spotted spiders. Spiders in the family Theridiidae are generally medium to small in size, and are named after their spherical abdomens. Most species lay large amounts of eggs.

In terms of body shape, the "black widow" has two outstanding characteristics: one is that its whole body is black-brown, with funnel-shaped red spots on the abdomen, which is why it is called the interspotted spider; the second is that the individual is not large, with a single one being more than 10 mm long and usually weighing 1-3 grams. The female spider is larger and more poisonous than the male spider.

The small but poisonous "black widow" (Photo source: Chinese Animals)

The difference in size between male and female spiders is related to the name "black widow". It turns out that after mating, in order to restore physical strength and maintain nutrition during pregnancy, the female spider uses its large size to eat the relatively weak male spider, making itself a "widow" in advance. The smart male spider slips away before the end of mating and never meets the female spider again. In this way, the female spider also becomes a true "widow".

The ruthless black widows are found all over the world, especially in America, where more than 2,000 Americans are bitten or killed by them every year. There are two types of black widows in my country, the interspotted black widow spider and the American black widow spider, which mainly live in Xinjiang and Yunnan.

The "black widows" seized by Xiamen Customs are foreign species. They were secretly hidden in the corners of containers and traveled across the ocean to China.

Neurotoxins kill people

As a poisonous spider on par with the brown flat-armored spider, Australian funnel-web spider, black-bellied comb-legged spider, etc., the "black widow" is a ruthless character. Its toxicity is more than 10 times that of rattlesnakes and Suzhen kraits, and its mortality rate can reach 10%. ("Fauna Sinica - Arachnida - Theridiidae")

The venom glands of the black widow are very strong, and the venom contains more than 80% neurotoxins, which can cause the "inactivation" of neurotransmitters. Neurotransmitters are the "little messengers" that transmit information between the nervous system and muscles.

Under normal circumstances, neurotransmitters transmit messages back and forth between the nervous system and muscles, allowing muscles to move correctly. When the "Black Widow" injects venom into the human body, the neurotoxin, which is larger than the neurotransmitter, blocks the channel connecting the nervous system and muscles. The muscles cannot receive instructions from the brain and nervous system, so the human body cannot move. For example, if the joint between two pipes in a sewer is blocked, water will naturally not flow.

If you are stung by a black widow, you should stay calm, stay away from the spider bite before your body becomes numb, remember the spider's markings and color, and "remove all restricted items from the injured area, such as rings, bracelets, watches, etc., to avoid subsequent swelling that makes them unable to be removed, which will aggravate local damage. Early pressure bandaging will help slow down the absorption of toxins, and the wound should be rinsed with clean water nearby. The patient should be transferred to a hospital for treatment as soon as possible, and vital signs should be observed during the journey." (People's Daily, author Wang Chuanlin, chief physician of the emergency department of Peking University People's Hospital)

During the treatment process, do not suck out spider venom with your mouth like in movies and TV shows. This is because the "black widow" is not only extremely toxic, but also poisonous all over the body, including the legs, abdomen, eggs, etc., and people who suck it are very likely to be poisoned.

Invasive species have serious consequences

The reason why the "black widow" intercepted by Xiamen Customs has attracted widespread attention is that, in addition to being extremely toxic and harmful to humans and animals, it will also change the local ecosystem and even cause genetic mutations.

There are two reasons for the change in the local ecosystem. The first is the high reproductive capacity. Like the equally notorious red fire ants, the "black widow" is also a high-reproduction creature. The characteristics of this type of creature are that it has a short lifespan and a strong ability to spread. Female "black widows" can continue to lay eggs after mating once, and the number of eggs laid in a lifetime can reach up to 5,000, and small spiders can hatch within 3 months. This reproduction speed is difficult for humans to control.

The second reason is that there are no natural enemies.

The lack of natural enemies is one of the main reasons for the destruction of the ecosystem. The black widow has very few natural enemies, which are mainly concentrated in the western United States, such as alligator lizards and western geckos.

After invading Fujian, the invincible "black widow" generally does not integrate into the local ecological food chain. Instead, it preys on flies, moths, crickets and other small animals in large numbers, causing damage to the existing ecosystem and even creating a species vacuum. Without natural enemies to restrict it and with strong reproductive capacity, the "black widow" will become a disaster within a few years.

There are precedents in this regard. For example, the Canada goldenrod that invaded my country has a strong reproductive capacity and spreads quickly. No animals are interested in it. It actually competes with local crops for nutrients and water, causing a decline in crop quality and yield, posing a serious threat to biodiversity. In recent years, news about the removal of Canada goldenrod has also emerged one after another.

In addition, the invasion of black widows from other places may also cause genetic mutations in local species. They may hybridize with local venomous spiders and produce spiders that are more venomous than black widows.

There are many examples of this. For example, the killer bees that killed more than 1,000 people are the result of a cross between Brazilian honey bees and African honey bees. Therefore, the mutant spiders that chase people in science fiction movies are not without scientific basis.

Poisoning humans and animals, changing the ecosystem, causing gene mutations... The seemingly insignificant "black widow" has such terrible consequences when it invades our country. While we are amazed by this, we also want to say thank you to the Xiamen Customs staff who carefully seized the "black widow"!

【References】

1. Fauna Sinica, Science Press, January 2016.

2. Paper “Clinical Research and Progress of the Toxin of the Interspotted Spider”, authors Liu Juanjuan, Dong Xinling, Sun Hui, Kou Xiaowen, Xinjiang Medicine, Issue 1, 2015.

3. Paper "Diversity and Functional Analysis of Toxins in Egg Granules of the Interspotted Spider", author Xu Dehong, Journal of Hunan Normal University, Issue 2, 2019.