There are many animals in the biological world that are venomous, but not all venom is created equal. Some stings and bites are merely irritating; others can stun their victims slowly and unexpectedly. Then there are those stings that cause extremely high levels of pain. Here are 10 of the animals that deliver some of the most painful bites or stings in nature.

1 of 10 Platypus worldswildlifewonders / Shutterstock Considering the large number of venomous creatures that inhabit Australia, the cute and clumsy platypus might seem like a safe option. Unfortunately, it isn’t always. A male platypus has ankle spurs on its hind legs that are capable of delivering a sting that can cause excruciating pain and swelling in humans. However, platypuses usually do not sting humans unless provoked, they primarily use their venomous spurs as a defense against rival males of their species.

2 of 10 Gila Monster Kris Wiktor / Shutterstock Gila monsters, one of the few venomous lizards in the world, are colorful natives of southwest North America. Since they lack the musculature to forcibly inject venom, they rely on hard chewing with their sharp teeth to ensure that the poison gets implanted. Gila monsters can be so aggressive that they have been known to flip over while biting, further opening the wound. A Gila monster bite will cause pain in humans, but fortunately these creatures are mostly docile toward humans as long as they are left alone.

3 of 10 Black Widow Spider Jay Ondreicka / Shutterstock One of the world's most notorious spiders, the black widow lives up to its reputation and is capable of delivering a bite that is both painful and toxic in humans. Early symptoms of a female black widow bite may be minimal like a pinprick, or not felt at all. Within an hour, symptoms may include pain throughout the body near the site of the bite, difficulty breathing, high blood pressure, muscle weakness, nausea and vomiting, and, in pregnant women, contractions and early labor. Interestingly, bites from male black widow spiders, which are smaller and less colorful than females, are less harmful as they contain less venom.

4 of 10 Stingray Yann hubert / Shutterstock The creature that killed Steve Irwin isn't usually a threat to humans, but it will strike if threatened. Stingrays have sharp barbs containing venom on their tails; and most injuries occur when someone steps on one accidentaly. Effects of a stingray encounter usually occur within six to 48 hours and are rarely fatal. Symptoms may include breathing difficulty, sweating, and chest pain. To avoid being stung by a stingray’s sharp barbs, shuffle your feet as you walk through the sand in shallow water.

5 of 10 Tarantula Hawk Wasp Elizabeth A.Cummings / Shutterstock Tarantula hawk wasps are huge, and their name is derived from their habit of hunting tarantulas. After stinging a tarantula, the wasp lays its eggs on the spider and buries it. Because tarantulas are not easy prey, tarantula hawks are equipped with a powerful venom that is reputed to create one of the most painful stings in the insect world. According to the Schmidt Sting Pain Index — a pain scale rating the relative pain caused by some insect stings — a sting by a tarantula hawk rates as the second most painful sting ever measured.

6 of 10 Stonefish Gerard Soury / Getty Images Not every creature on this list is capable of delivering a painful sting that can kill you, but the stonefish is one of the exceptions. Stonefish are the most venomous fish in the world, capable of delivering fatal stings to humans. Unfortunately, stonefish are also masters of camouflage, blending in with their surroundings on the ocean’s floor or on coral reefs. Stonefish have spines along their dorsal fins that contain venom. A sting from a stonefish requires medical attention and treatment with antiserum to reverse the symptoms which may include irregular heartbeat, temporary paralysis, shock, extreme pain, and possibly death.

7 of 10 Pit Viper David Kenny / Getty Images Pit vipers, which include copperheads, water moccasins, and rattlesnakes, are venomous snakes. In the U.S., copperheads are responsible for the most venomous snake bites annually, primarily due to proximity to human habitats. Of all the North American pit viper species, however, the venom of copperheads is among the least toxic. While a copperhead snake bite is not often deadly, it can cause severe pain within a few minutes of the bite. Symptoms of bites by all species of pit vipers may include changes in heart rate or rhythm, difficulty breathing, numbness near the site of the bite, swelling of lymph nodes, and weakness or dizziness.

8 of 10 Arizona Bark Scorpion EdwardSnow / Getty Images Arizona bark scorpions are the most venomous scorpions in North America — a frightening fact considering that they are also the most commonly encountered house scorpion in Arizona. The venom causes acute pain and can lead to symptoms including, frothing at the mouth, breathing difficulties, and muscle convulsions. Limbs may also become immobilized. Though the venom is rarely fatal, its effects can last for as long as 72 excruciating hours. Arizona bark scorpions tend to hide in dark crevices during the day and hunt at night.

9 of 10 Box Jellyfish Billy Huynh / Getty Images These gelatinous sea creatures, also called sea wasps, are among the most feared animals in the ocean. You might have a better chance of escaping a shark attack unscathed than surviving a swim through a box jellyfish's tentacles. The venom is so toxic that it is reputed to be the most venomous creature in the world. Within five minutes of being stung, humans typically experience extreme pain, shortness of breath, and sometimes cardiac arrest. Researchers are working on an antidote to block the effects of a box jellyfish sting; which can be effective if applied to the skin within 15 minutes of the sting.