This absolutely beautiful spider is Ruby, a MEXICAN RED KNEE TARANTULA.  This is the species of tarantula which most people are familiar with from pictures or on television/films, as it is one of the most popular species of all due to its colouration.  I acquired Ruby in September 2007 when she was still a juvenile and she has grown a lot since then and become very attractive indeed.  She is very calm and friendly too as anyone who has met her will know!

It is very unfortunate that tarantulas have such a bad reputation for being nasty and dangerous creatures as it just is not true.  Despite being venomous they are really not dangerous to people at all and rarely if ever bite people, despite films often showing them doing this.  If a person is bitten by a tarantula the effect is usually no worse than a bee sting as their venom is very weak, so they are not at all the deadly creatures that many people believe them to be. 

Tarantulas are actually generally shy and secretive animals and many spend their days hiding under logs etc. or even underground in burrows they create for themselves, but thankfully Ruby here likes to be on display in her enclosure at all times!  In the wild Mexican red knee tarantulas spend a lot of time in their deep burrows where they hide from predators such as the coati.

To date Ruby has moulted five times since I bought her in September 2007, the moulting process being one of the most fascinating things about tarantulas as they completely renew the whole of their outer body or exoskeleton whilst somehow leaving their old exoskeleton in one piece!  The picture below shows the scene which greeted me on the morning after her most recent moult at the end of March 2010:

It is always a remarkable and unusual sight as it looks like there are two tarantulas, but the one on the right of the picture is nothing more than the empty outer body (exoskeleton) which the real Ruby (on the left) has squeezed herself out of!  The empty exoskeleton is less colourful, or at least more brownish in colour, as Ruby has renewed all of her black and red/orange hairs during the moulting process! 

The pictures below show her moulted exoskeleton, looking remarkably like her but being nothing more than an empty case or skin, which is correctly called an exuvium.  I have very carefully positioned it in a plastic tub so as not to break it as it is very brittle and easy to damage.  The left hand picture shows the exuvium with the carapace (head) in place, whereas on the right it has been 'flipped back' to reveal the inside:

It is through the openings in the central part of the body (underneath the carapace) that the tarantula has to pull all of its new legs and fangs, a truly remarkable achievement.  You can see these openings more clearly in the two pictures below, with carapace intact first and then removed in the second picture!

Each opening leads into a hollow tunnel and the new legs and fangs are pulled out of these during the long process of moulting, which can take several hours to complete.  I have always said that this is one of the most remarkable sights in the natural world and I stand by that claim again today, it is a sight I never tire of seeing!

The two pictures of Ruby's head area below clearly show the difference in colouration she is showing following her recent moult.  The first picture was taken in April 2010, three weeks after her most recent moult, and the one below in July 2008.  Both the greater depth of the blacks and higher intensity of red/orange colouration in the top picture are very clear to see, and although I've always thought of her as being attractive I think she is absolutely stunning now due to the much higher contrast between these colours!

If you look at the picture above very closely you can also see six of her eight eyes!  The eight eyes of a tarantula are arranged in a cluster around a small mound at the front of the 'head', or carapace as it is correctly named, but despite having so many eyes they do not see very well at all.  Instead they rely on the very sensitive hairs on their legs to detect movement and change in their environment, and they even have highly specialised leg hairs which can 'taste' the air!

The simple truth is that tarantulas are fascinating to watch grow and also very beautiful animals to look at and admire, which I hope you can see is definitely the case for the lovely Ruby!