These truly remarkable animals are known by two interchangeable common names, WHIP SPIDERS and TAILLESS WHIP SCORPIONS, and they are probably my favourite group of arachnids in the world! Whilst they are arachnids, like spiders and scorpions, they are neither true spiders or true scorpions but represent a distinct group known as the Amblypygi. This particular species is native to Tanzania in east Africa. 

Their pedipalps or ‘pincers’ are of a very different structure to those of scorpions, although like scorpions they are still used to catch prey and are covered in sharp spines as you can see above.

When a whip spider is at rest, as in the pictures above, these pedipalps are folded in on themselves and are a bit like arms fully bent at the elbow. When the whip spider is defending itself, hunting or communicating with other whip spiders these pedipalps will sometimes be opened up as in the pictures below:

You can easily tell males from females in this particular species of Tanzanian tailless whip scorpion because the males have much longer pedipalps. In the pictures below the male is on the left, with pedipalps which extend well beyond the first ‘knee’ joint of the first pair of walking legs, whereas the female’s (on the right) do not extend past the ‘knee’ joints at all:

You can also see this difference in this picture of the two of them together, again with the male being on the left hand side:

Tailless whip scorpions have very special front legs which are much longer and thinner than the other legs. These front legs are actual special sensory legs and are not used for moving around at all, whereas the other six legs are used for walking (or running when required)! These incredible front legs have lots of sensory receptors so that when they probe around as they walk through their habitat they can detect the tiniest vibrations or movements made by potential prey items, before the pedipalps are used to grab them. They are so long that in the picture below not a single one of this pair’s four front legs even fits fully into the frame of the image!

In December 2013 I had the privilege of encountering a different species of tailless whip scorpion during my amazing trip to the rainforests of Costa Rica and it was absolutely fantastic to witness them hunting in darkness in the wild. Here are a couple doing exactly that – these pictures were taken in total darkness and are only lit up due to the light from my head torch:

Even wild individuals do not demonstrate any signs of aggression to humans and I was able to handle several individuals without any problem at all.

I am very fortunate to have had breeding success many times within my own collection, first way back in February 2011 with my original pair named Bob & Kate. They produced many clutches before passing away and one of their male offspring (Mr Whippy) has fathered several clutches including the most recent batch in September 2023. When a female whip spider lays her eggs she then carries them on the underside of her abdomen, inside (and protected by) a thin membrane. Here is a female carrying eggs soon after they have been produced:

As the eggs develop they darken inside the abdomen and end up looking like this:

Here you can see the tiny green and pink babies emerging from the underside of the female’s abdomen – always an exciting moment to catch on camera!

Once the babies have all emerged from their eggs they attach themselves to Mum’s abdomen, as seen below:

What isn’t clear from these pictures is that there are actually babies being carried on the underside of the abdomen as well, so the number of babies in one clutch is even greater than it would first appear. I personally think that the babies are absolutely adorable, but no doubt many people would not agree with me about this!