There are more than 1,200 different species of tarantulas worldwide. These tarantulas are all very different; they vary in size, behavior, and looks.
What you will find is that tarantulas are separated into two fundamental groups—old world tarantulas and new world tarantulas.
So what is the difference between the old world and the new world tarantulas?
The main aspects that make old world tarantulas unique are that they are more aggressive, defensive, faster, and have more potent venom. The more docile temperament of new world tarantulas also makes them more beginner-friendly in comparison with the old world tarantulas.
In this article, I will take a more in-depth look at the differences between the new world and old world tarantulas. As it stands, looks can be very deceiving, and tarantulas can be very different. Let’s take a look.
The Area of Origin
The terms new world and old world actually denote where these species of tarantulas come from.
New world tarantulas are native to the western hemisphere. They are found in the regions of North and South America.
In comparison, old world tarantulas are native to the eastern hemisphere. They are found in the regions of Europe, Asia, Africa, and Australia.
In fact, this is where the name of the two groups of tarantulas is derived from. Europe, Asia, and Africa are known collectively as the old world. And the Americas are collectively called the new world—with the exception being Australia, which is also considered part of the new world.
The biggest difference between the new worlds and old worlds is their behavior.
Although there can be many exceptions to the rule, old world tarantulas will often be more aggressive than new world tarantulas. Old world tarantulas do not like being bothered and do not take lightly to having their habitat disturbed. They are more nimble and lively, and their behavior can be a little more erratic, moody, and unpredictable.
New world tarantulas, on the other hand, are more docile and easy-going; they would prefer to hide than to immediately attack.
It is hard to pinpoint one exact reason why old world tarantulas are more aggressive.
Old worlds may be more aggressive simply because they may have been exposed to a higher number of predators over the years, the climate where they live may be more unforgiving, or simply because they do not have urticating hairs. (More on that in a bit.)
That being said, just because it can, a tarantula will not bite you for no reason. A tarantula (and any other species of spiders, in fact) will bite only after it has been provoked in some way or if it feels threatened.
However, let me stop you right there as I believe something more needs to be noted. To a certain degree, the belief that old world tarantulas are more dangerous and aggressive than new world tarantulas is based largely on a stereotype, which may or may not be based on solid facts.
Often people will disturb their tarantula or flat out provoke it in some way resulting in more aggressive behavior and, possibly, an accompanying bite.
In many instances, we can observe very different behavior from both new world and old world tarantulas.
For example, old world tarantulas may prefer to run away and attack only when cornered and have no means of escaping. At the same time, new world tarantulas may decide to attack with all they got right from the beginning and not be as aggressive as old worlds once cornered—or often, they may not do anything at all.
It is important to understand that tarantulas are all individuals.
Just because there is an expectation that a certain tarantula species is more aggressive does not necessarily mean that all are or ever will be.
The Venom Potency
Upon comparison, we will find that the venom of new world tarantulas and old world tarantulas also differs in its potency and strength.
Old world tarantulas will usually have more potent or poisonous venom. This makes their bites a little more dangerous and more painful.
Normally old world tarantulas venom is not dangerous unless you are allergic to it. However, it is very potent, and a venomous bite from an old world tarantula can result in severe localized cramping and pain that can last several days and, in certain cases, even fever or nausea.
In addition to that, they can also be very dangerous to pets and other animals, which asks for extra care and attention if you have other pets living in the same home.
On the other hand, the venom of new world tarantulas is weaker and often reminiscent of a bee sting in strength.
Not all tarantula bites will hurt the same, while some tarantula’s bites will be weaker and less painful, others can really pack a punch. (Two good examples of tarantulas that you do not want to get bitten by are the Pterinochilus murinus and the Poecilotheria regalis.)
However, it is worth mentioning that not all bites will contain active venom being injected. Often tarantulas will prefer not to use any venom at all—this is known as dry bites. Although this makes dry bites less dangerous, it does not make them less painful.
This brings us nicely to the next difference between the new world and old world tarantulas.
The Means of Defense
Old world tarantulas are not only more aggressive in nature but also have bigger fangs compared to new world tarantulas.
But biting is just one of the ways tarantulas can defend themselves.
The second way some tarantulas can attack is by flicking their tiny hairs found all over their abdomen.
Those small hairs known as urticating hairs are like tiny arrows that can get in your eyes, skin, and nose, causing localized swelling, which can potentially be dangerous if you are allergic or if you breathe them in.
However, if those hairs get stuck in your skin and you are not allergic, the result is usually a mild itching sensation that should last no more than a few hours.
While some tarantulas will have relatively benign hairs (like the Brachypelmas), others (like the Lasiodora parahybana, Nhandu chromatus, or the Theraphosas) will have hairs that can cause a stronger reaction. The reaction to tarantula’s hairs can also vary from person to person due to individual sensitivity.
Interestingly enough, this intricate defense mechanism is found only in new world tarantulas and not old world tarantulas.
Not all animals are suitable for beginners. While some can be a great beginner-friendly pet, others will be reserved only for the more experienced owners.
And one of the first things that people interested in owning a pet tarantula should look for is a beginner-friendly tarantula.
Not all tarantulas will be suitable for a beginner.
Old world tarantulas are recommended only for owners that have previous experience caring for a tarantula. Because of their more aggressive and unpredictable behavior, old world tarantulas are harder to care for, and a beginner may find them very difficult to look after.
Since old worlds are also very quick on their feet, this can pose some problems that many people may overlook at first.
When they move in for a kill or try to defend themselves, they are extremely fast and can move quicker than most people can react. This can make routine actions like cleaning the tank or replacing the water bowl very tricky and unpleasant.
In comparison, new world tarantulas, due to their more docile nature and less potent venom, are easier to care for; thus, any first-time tarantula owner is strongly recommended to go with a new world tarantula as their first tarantula.
It is worth noting that despite their easy-going nature, new world tarantulas’ urticating hairs can make them unsuitable to people who have allergic reactions to their hairs.
A lot of people will be worried about the dangers of urticating hairs on new worlds, but they are fairly benign. In most cases, you shouldn’t be so close that those hairs will get into your eyes or nose, so if anything, it may be your hands that will be at risk. Conversely, some owners have reported that the longer they have been exposed to tarantulas urticating hairs, the more sensitive they tend to become to them.
However, before kicking their hairs, tarantulas need some time to prepare (one to two seconds on average), during which you should be able to safely react and move your hands out of the way.