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Costa Rica Poisonous & Venomous Spiders, Snakes & Other Insects

Venomous Spiders & Snakes

Venomous Spiders & Snakes

Many peoples vacations in Costa Rica in central America have become awash with venomous snakes, poisonous spiders, and flesh eating bugs, as well as blood suckers.

Costa Rica may be beautiful, but to the unwary person on vacation in Cost Rica, there may be problems ahead, as thousands of biting insects and animals await their next meal. There are not many reports of finding large spiders in hotels, but it does happen.

Beautiful Costa Rica is a lavish wilderness which attracts millions of visitors every year without any hindrance or accidents. But, poisonous animals cause fatalities, blindness, and severe breathing difficulties as well as temporary paralysis and leaves people in need of medical attention to have a limb amputated.

Being warned is being forearmed. Prior to leaving home for a vacation in the Costa Rica, ensure all members of the family have their inoculations required for this country.

Brazillian Wandering Venomous Spider

Brazillian Wandering Venomous Spider


The Brazilian Wandering Spider

This rather large spider was entered in the Guinness Book of Records in 2010 as the worlds most venomous spider. The leg span on this hairy spider can be as much as 4 - 5 inches ( 13 - 15 cm ) and the body is approximately 5 cm.

This poisonous spider is found throughout central America, and due to the amount of small villages and individual tribes, it can never be discovered exactly how many people have died from the bite of this spider. Several tourists on vacation in the Costa Rica have been bitten by this spider and have had their lives altered completely.

Just finding one of these spiders in the hotel room is enough to give anyone a heart attack. The venom is a very potent neurotoxin.

After being bitten, a victim will initially find a redness and inflammation around the bite mark. Soon, breathing may become difficult and slight loss of muscle control in the body will take hold.

Partial or total paralysis will begin to envelope the body as muscle control is totally lost and pain racks the body. After this, a slow asphyxiation prior to coma, then possible death. Cheap hotels in Costa Rica may check the rooms periodically for dangerous insects and spiders, make sure you do as well.

Some male victims who do not die from this bite, may find they cannot help but get a painful erection, but it can cause impotency. Scientists are now using this spider as a means to help patients with erectile dysfunction. There are also many Tarantula Spiders in Costa Rica, but their bite is not considered too dangerous.

Untreated Spider Bite

Untreated Spider Bite

The Black Widow Spider

There are nearly 2000 species of spider in Costa Rica, most spiders will only use their venom to paralyze their prey and do not attack or bite humans. The black widow spider is relatively the same, but will only attack if provoked or frightened. The Black Widow spider has found its home nearly all around the world as climate changes make many countries more favourable for their breeding habits.

If bitten by this spider, a persons limb may swell to three times the normal size. If a person is bitten by any spider, it is always advisable to seek medical attention just in case. These spiders can be found in many hotel rooms, hostels and other places inhabited by humans

Please follow the free link for information on the Brown Recluse and the Black Widow Spider which can be found in the Costa Rica. The wounds caused by these spiders could become infected if not treated and cause gaping wounds of 20cm across and 2 cm deep in the human body. These bites usually do not kill, but they are very painful and can ruin a holiday.

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Central American Coral Snake

Snakes make up nearly half of the reptilian life on the Costa Rica, with 135 species of snakes and of these 17 are venomous. The Central American Coral Snake averages about 65 cm ( 26 inches ) but they can grow to in excess of 45 inches. The coloring can vary between two or three colors with black, red, and yellow banding along the length of the body.

This ground dwelling snake can be found in soft earth, rock piles and under logs amongst many other things. The venom injected by is neurotoxin, and is one of the most potent toxins of any Central American snake, with a reported 25 bites (approximate ) per year on humans.

The fangs are quite small and cannot penetrate thick clothing such as leather, but if the skin has been punctured, medical assistance will be required immediately. A person may die within hours of being bitten from respiratory failure if anti-venom is not administered.

In the USA, it has become to expensive to produce anti-venom for the bite from this poisonous snake. So there will be very little or no anti-venom available. A foreign company is developing a new anti-venom, but to license this in the US may also be financially un-viable. Hotels should warn their patrons on vacation if these snakes are in the area.

It may be prudent of any person seeing one of these snakes to avoid it at all costs. They are usually found away from human habitation in rural or forested areas. Campers and hikers are more at risk and should take extra care.

If bitten, artificial respiration may be neccesasry to help prolong or save the persons life. This venomous snake is dangerous, and the lack of anti-venom, potentially makes it the most dangerous snake. Vacations in the Costa Rica may result in death is the tourist does not have their witts about them.

Fer-de-Lance Venomous Snake

Fer-de-Lance Venomous Snake

Fer-de-Lance Snake

This beautiful but venomous snake is also known as the Common Lancehead, and the Barba Amarilla. Growing to 125cm, this predator usually feeds on small birds, frogs, rats, mice, and other smaller snakes.

Colour schemes vary from olive to gray, and the body markings can range from vivid to blurry with rectangular or triangular patterns. Because of this wide variety of body markings and coloring, these snakes are easily confused, but they are dangerous.

The snakes will lay silently for hours waiting for their prey, and then strike with amazing speed and agility. Many plantation workers are bitten whilst working the fields, and if medical attention is not received rapidly, fatalities have occurred.

Each female snake will give birth to approximately 60 live young, three times a year.The venom injected by the Fer-de-Lance snake is hemotoxin. Never usually found inside hotels, but it could happen.

Victims of a snake bite from this creature may be treated and recover if anti-venom is received quick enough. Initially bite victims may feel nauseous and have blackouts with temporary paralysis. In nearly all victims, either temporary or permanent short term memory loss happens. Lengthy hospital stays and weight loss of up to fifteen pounds have been recorded.


Poison Dart Frogs

These tiny, beautiful, yet extremely potent reptiles were once used by tribes to poison their enemy. The poisons secreted from the frogs skin is potent enough to kill 20 humans at once, or over 10,000 mice.

Natives smeared their spear and arrow tips on the frogs body before going off to war with local tribes. Once the arrow or spear impaled a person, even in the hand, that person was as good as dead within minutes. There are over 175 species of this poisonous frog, although only three were used to poison arrow heads.

These frogs come in magnificent vivid colors and are easily distinguishable in the forest. They weigh in at only 2 grams each and are 2.5 cm in length. The Golden Poison Frog is the most potent of the Poison Dart Frogs and will produce enough poison in a lifetime to kill up to one thousand humans.

The poisons secreted vary greatly from one species of poison frog to another. Generally, a person who has handled one of these frogs will suffer from partial paralysis as the poison restricts and prevents nerve impulses to the heart, causing heart attacks and may stop the heart from functioning completely.


Bullet Ants

This magnificent insect is named after the potent sting that it delivers, it is like being shot with a bullet. The sting from this 3 cm ant is revered to be the worst in the world and usually leave the victim in tormented pain for 24 hours.

The pain is so intense that some people pass out.

Each bullet ant nest has approximately 700 ants, and there are 3 nests per hectare. Nests are usually found under trees and shrubs, but the wandering ants can be found almost anywhere. No deaths from this ant have been recorded, but many thousands of tourists have been injured. Local coming of age ceremonies include a young man being bitten five times by these ants to show their bravery.

Costa Rice is an exceptionally beautiful place to visit, but as with many tropical climates, migrating insects may cause problems. Always be prepared and be cautious and never go into the wilderness alone. The beaches are exotic with warm crystal clear waters lapping gently on the sand, just watch out for the many Poisonous and Dangerous Sea Creatures which also lurk in the waters off the coast.

Biting Poll


Dick Gordon on June 18, 2019:

I was scared by Fortnite

Alesia philips on August 31, 2018:

FIRE ants mosquito' ants are fairly small the attack in bunches their bite leads to a red upraised bump which fills with puss the bite leaves a mark that does not go away I have been bitten several timrs by them and after 5 years can show the marks from the bites

El Ave on July 25, 2016:

Chiggers by far are the worst thing I have encountered here. you can't see them they are so small. They live in grass and on plants and in the soil. and itch like crazy. people erroneously call them no see ums. They leave a red dot that takes weeks to heal. I have seen very large spiders in my houses several times but never been bit a friend of mine was. It bit his leg and the bite area was swollen and red and very painful but he recovered . And many times very small ants which are everywhere, these pack a very intense painful bite but does not last more than a few minutes. Bring baking soda for bug bites make a paste out of baking soda and water for relief of itching. mosquitoes are few where I live and not that bad. But the chiggers are the worst, they attack legs mostly so wear long pants and shoes in grassy mountainous areas. a few bites from these can keep you awake at night with intense itching.

Kay on April 30, 2016:

Ummm I have never encountered anything remotely dangerous here in THE Costa Rica lol just smelly bums in San Jose. Unless you are rolling around in the forest a few days, you should be fine

Robert Haile on December 22, 2015:

Over 30 years we have been bitten by everything except snakes.

chelsie on July 28, 2015:

this was very helpful imformation

Joni on April 07, 2015:

Not sure what got me while in a covered waterslide in the woods. It stung me in the left abdomen, and felt like a burning hot, painful sting. Blinded by water, and trying to hold on to my rubber tube, I tried to sweep it away and felt a long chitinous thing with a thin waist which got between my fanned fingers and fought violently to escape. Thought it was a giant wasp, but apparently, these don't exist in Costa Rica... The burn was very painful and red, and treating it with two pads of "After Bite" only made the pain, which lasted for days, more manageable. Since then, I have had problems with recurrent numbness in roving areas on my left side. Still don't know what it was...

Mike on October 28, 2014:

Only ticks bit me in the Costa Rica rain forest. Which are less dangerous there than in my own country (Holland).

David King on October 26, 2014:

I don't have anymore intentions of being bitten ever again once by a brown recluse is enough. Almost bitten by a cottonmouth. Recluse had to go to the doctor and have the bite cut open and cleaned out painful.

China on June 12, 2014:

I was bit by a human

Julie on May 04, 2014:

I was stung by a large black scorpion whilst walking / climbing in the rainforest in Costa Rica. It was a very strange experience. It was painful and made me dizzy but all effects cleared after 2 days.

shelly ann on August 07, 2013:

A friend od\]]]]]]\

A friend of mine said that a spider bit his horse and the horse died of an infection

. Is this true?

Ryan on January 20, 2013:

was bitten by bot flys notnsomething you want.

brian maynard on November 15, 2012:

I am just wondering if large brown tarantulas are poisonous in the Nevada desert. Just got a big one in my back yard, going to take a picture and release it in a few mins i was just wondering if you read this please reply.

Geoff McCabe on June 13, 2012:

Check out this video I shot of a Brazilian Wandering Spider in Malpais, in the southern Nicoya Peninsula:

Karolyne on April 08, 2012:

3 times by scorpions. Countless times by ants. Sure don't like the feeling.

I live here ( Nicoya Peninsula) in the mountains 7 months a year, so believe me, scorpions, bugs, insects...rule my property. But hey! that's the price to pay to live in Paradis.

Pura Vida!

miguel h on February 24, 2012:

I want to know more about posenus

Dart frogs and snake's and spiders

Souvik Mukherjee from Bangalore, India on September 05, 2011:

A very informative hub. Since I love animals and reptiles knowing more of these species is indeed a boon! Thanks for the information!

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