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 a distinct group known as the amblypygids.  This particular species is native to Tanzania in east Africa.  The pictures below are of my adult pair named Bob and Kate! 

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 here:

When a whip spider is at rest, as in the first picture below, these pedipalps are folded in on themselves and are a bit like arms fully bent at the elbow:

When the whip spider is hunting these pedipalps will sometimes be opened up ready for action, as in the picture 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 Bob the male is on the left, with pedipalps which extend well beyond the first 'knee' joint of the legs, whereas Kate'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 Bob being on the left hand side:

In the picture below you can see that Bob & Kate's front legs are much longer and thinner than their other legs.  These front legs are actual special sensory legs and are not used for walking, whereas the other six legs certainly are used for walking (or running)! 

These front sensory legs are very thin indeed and have lots of sensory receptors, so that when they are used to 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! The picture below shows just how long they are, with none of the sensory legs even fitting fully into the frame of the picture!

When a female whip spider lays her eggs she then carries them on the underside of her abdomen, stuck underneath (and protected by) a thin membrane!  Here is Kate carrying her latest batch of eggs in February 2012:

These eggs are due to hatch at some point in the late spring / early summertime of 2012, watch this space for more news...

When the eggs hatch the babies climb onto the abdomen itself and grip tightly to it.  On February 20th 2011 I was absolutely delighted to find that Kate had babies all over her back, this being the first time that I had successfully bred tailless whip scorpions! 

What isn't clear from these pictures is  that there are actually babies being carried on the underside of Kate's abdomen too, so the number of babies is even greater than it would at first appear to be!

I personally think that the babies are absolutely adorable, but no doubt many people would not agree with me about this!!!

Within 10 days of hatching every one of the babies (which turned out to be 57 in number, many more than I was expecting) had moulted for the first time and climbed off of Kate's back. After moulting for the first time they look very different from the 'tiny blobs of jelly with legs' in the pictures above as you can see here, with beautiful patterns and colouration too! 

This next picture shows very clearly just how amazingly long their front 'feeling' legs are even as tiny babies!

From this point onwards they are independent and able to fend and feed for themselves although they are quite sociable creatures and are known to sometimes live together in family groups, consisting of animals of different ages, at least until they reach maturity.  Here are pictures of just some of them exploring the pieces of bark in their new home:

When I discovered that they had left Kate's back I also found a huge pile of moulted exoskeletons (exuviae) on the floor of their enclosure - here are just a few of them, looking more like something out of a science fiction film or maybe a portion of crispy noodles!!

Within five weeks of hatching (end of March 2011) some of the babies had moulted again and were looking a lot more like their parents already!

The next two pictures are of one of the recently-moulted individuals next to its siblings which have not yet moulted, showing the impressive size difference which the moulting process brings about!  In both cases the newly-moulted individual is on the right hand side of the picture:

By May 2011 the babies were at an even larger size as you can see from these pictures below!

By late August / early September 2011 (at just over six months old) they had grown much larger still as you can see here, it is really hard to refer them as 'babies' once they get so large!

Here are three of the exoskeletons moulted by the 'babies' in late August / early September 2011:

Here is a picture of one of the females on her first birthday, February 20th 2012! 

Whip spiders, like all arachnids, have to moult their exoskeletons regularly during their development.  Kate moulted most recently in August 2010 and Bob moulted in March 2011.  I was especially lucky to get some pretty amazing photographs of Bob very soon after moulting.  I was just doing my usual late evening checks of all my animals when I found the scene below:

What you are looking at in the above picture is Bob's empty exoskeleton (exuvia) hanging from the mesh roof of his & Kate's enclosure, with Bob himself being the very pale white shape just behind and to the left of the exuvia!  After moulting a whip spider's brand new exoskeleton is very soft & extremely pale in colour and they hang upside down for a time to allow it to begin the process of drying out. Here is Bob photographed VERY soon after moulting, looking quite amazing as you can see!!

Here are a couple of pictures of one of the babies when also newly moulted, looking like a tiny version of his or her dad in its freshly-moulted colours!

When newly moulted they look very different to their normal colouration as you can see here!

During the drying out process the colouration of a whip scorpion's new exoskeleton changes dramatically, as it goes from the extremely pale colour above to their normal colouration.  This next picture is one of Kate taken just a couple of hours after her moult in August 2010:

As you can see she looked more like an alien than usual, amazing!  Sadly I didn't get a picture of Bob at this same stage as it would have meant staying up into the early hours of the morning!  When I looked in on Bob the morning after he'd moulted, just eight hours after the photo of him looking white was taken, his colouration had changed dramatically as you can see here!

I'm sure you'll agree with me that they look pretty amazing during this drying out process, with their bizarre mixture of greens and blues!!  Just 36 hours on from when I found Bob moulted his colouration was pretty much back to normal as you can see here:

The moulted exuvia itself is an incredible structure as it looks so alive despite being just an empty 'shell'!  Here is Bob's exuvia with the pedipalps (pincers) fully open:

They always manage to leave the exuvia completely in one piece following moulting, which in itself is quite incredible considering the complex structures which they have to pull out of their old body during the moulting process!  The pictures below are of Kate's exuvia with the first showing the 'head' (carapace) of the exuvia closed, the second picture showing it opened and the third showing the underside of the exuvia: 

As you can see it is really quite a remarkable structure and it is preserved perfectly.  Taking a closer look at the exuvia once the pedipalps have been opened you can see clearly the very sharp spines which are used in catching their live prey:

Whilst whip spiders are amazing predators and may look incredibly fearsome they really aren't at all!!  I personally handle these very regularly without any concern at all about being injured, as unlike scorpions they are not venomous and are non-aggressive.  I also regularly allow children to handle them as demonstrated here by 8-year old Ethan at his birthday party and 4-year old James at Sunbeams Pre-school in Calne! 

I'm sure you'll agree that tailless whip scorpions / whip spiders are quite amazing creatures, which in many ways are quite alien in their appearance, and you can trust me when I say that in the flesh Bob & Kate and their babies are even more amazing than they appear in these pictures!