The following list includes many animals extinct since the pleistocen age. Some of them are very similar to cryptids descriptions. For example, Big Foot to Gigantopithecus Blacki, Loch Ness monster to the Rodhocetus Balochistanensis and Thunderbird to the Teratorns.
See a picture here (http://www.bbc.co.uk/beasts/evidence/prog5/page5.shtml)
See a picture here (http://www.bbc.co.uk/beasts/evidence/prog1/page6.shtml)