Spider Molting: A New Start

It's 2016! Time to shed our old skin and start something new. As luck would have it our Brazilian black and white tarantula, Samba, molted over the holidays. Molting is the process by which an arthropod with an exoskeleton sheds its outer layer to reveal new cuticle. The new exoskeleton is soft and flexible. This allows the animal to pump some hemolymph (bug blood...ish) in order to stretch and grow a bit bigger. The shed exoskeleton is called the exuvia. What a great word. When I teach kids I tell them it's like when they out grow their sneakers. The sneakers that don't fit anymore are their exuviae.

Here's a snapshot of what the whole tarantula exuvia looks like. The head carapace pops off so we get a cool view of the internal structure.


Here's a ventral view. Spiders even shed the outside of their fangs! This is the only way we like to get a look at Samba's fangs. She is going to be about 7-9 inches in diameter (she was an impulse purchase).


It's time for a closer look!  For these next pictures I used the Celestron Flip View. I'm teaching some workshops at the National Science Teacher's Association in March with this little handheld scope. Here's a look at the internal structure where the legs meet. All of those pock marks are the insides of setae follicles.


Let's look at those fangs! One thing I love on tarantulas is the bright red and pink hairs that line the mouth under the fangs.


Tarantulas even shed the outer lining of their eyes! Here's a look at the inside of the head carapace, followed by a lateral view of the eyes from the outside.


Before they molt, tarantulas get a little sluggish and their colors are dull- but afterwards they are at their most vibrant! A great analogy for starting a new year with a vibrant new look or outlook. Check out the video below to see a time-lapse of Samba molting a couple of years ago. Happy 2016!