Capybara

Capybara is the largest living rodent in the world.Adult capybaras may grow to 130 centimetres (4.3 ft), and weigh up to 65 kg (140 lb).Though now extinct, there once existed larger capybaras that were eight times the size of modern capybaras (these rodents would have been larger than a grizzly bear)

http://en.wikipedia.org/wiki/Capybara

http://nationalzoo.si.edu/Animals/Amazonia/Facts/capybarafacts.cfm

http://www.bbc.co.uk/nature/wildfacts/factfiles/594.shtml

Blue-ringed Octopus

The blue-ringed octopus is the size of a golf ball, but its venom is powerful enough to kill humans. There is no known antidote.

http://en.wikipedia.org/wiki/Blue-ringed_octopus

http://www.earlham.edu/~sheedjo/blue-ringedoctopus.htm

http://www.didyouknow.cd/animals/octopus.htm

Mantis Shrimp

Called "sea grasshoppers" by ancient Assyrian , "prawn killers" in Australia and now sometimes referred to as "thumb splitters" by modern divers — because of the relative ease the creature has in mutilating small appendages — mantis shrimp sport powerful claws that they use to attack and kill prey by spearing, stunning or dismemberment. Mantis shrimp can break through aquarium glass with a single strike from this weapon.

http://en.wikipedia.org/wiki/Mantis_shrimp

http://berkeley.edu/news/media/releases/2004/04/21_shrimp.shtml

http://reefkeeping.com/issues/2004-03/jf/feature/index.php

Harpy Eagle

The largest and most powerful raptor found in the Americas, the Harpy Eagle has a body length of 35 - 41 inches, a 6 1/2 -foot wingspan, and weighs 10 - 20 pounds. The female can be as much as twice as heavy as her mate.

http://en.wikipedia.org/wiki/Harpy_Eagle

http://www.peregrinefund.org/explore_raptors/eagles/harpyeag.html

http://whozoo.org/Anlife99/coreybow/harpyeagle3.html

Chinese Paddlefish

One of the largest freshwater fish, it is said that the Chinese Paddlefish can grow to 23 feet and weigh 1,100 pounds, but little research on a maximum size can be conducted today due to the species' scarcity. Due to overfishing, the Chinese Paddlefish is endangered now and quite possibly extinct.

http://en.wikipedia.org/wiki/Chinese_Paddlefish

http://news.nationalgeographic.com/news/2007/07/070726-china-fish.html

http://www.capachi.com/paddlefish.htm

Giant Armadillo

http://en.wikipedia.org/wiki/Giant_Armadillo

http://www.kidsplanet.org/factsheets/armadillo.html

http://nature.ca/notebooks/english/giantarm.htm

Wolffish

The wolf fish is the largest fish in the suborder of blennies. Blennies are long fish that are similar to eels in appearance that have been dated back as far as 50 million years by fossil discoveries.

http://www.ocean.udel.edu/mas/seafood/wolffish.html

http://www.essortment.com/all/wolffish_rzkk.htm

http://en.wikipedia.org/wiki/Seawolf_(fish)