Liphistiidae are a family of spiders which don't have a common name.
These spiders are remarkable because they remain morphologically very similar to 290 million year old fossils from the same suborder. This means they have a very highly conservative body plan. Their venom glands are tiny and for a while biologists believed they didn't have them. They lack parts of the respiratory system which are present in all other spiders. They live in tiny tube-like borrows and make use of trapdoors like many other spiders.
Over the last 300 million years they have really got the whole trapdoor technique down packed.
Distribution:
Liphistiid spiders are found in East and South East Asia.
Classification:
Liphistiidae have been placed in a spider suborder called Mesothelae and are the only living spiders in this group. There are 3 extinct members of this group, all of which have a fairly highly conserved morphology. This suborder is the most basal group of spiders (i.e. it is the most distant relative of all other species of spiders). There are 8 genera in the family.
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Image Links:
http://en.wikipedia.org/wiki/Liphistiidae
http://www.qldaf.com/forums/spiders-insects-invertebrates-photo-video-lounge-95/liphistius-most-primitive-spiders-alive-76343/
Video Links:
https://www.youtube.com/watch?v=e3sDJnqj7hY