frilled lizard

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A large lizard (Chlamydosaurus kingii) of Australia and New Guinea having a broad contractile membrane extending from the neck and throat that can be erected like a ruff when the mouth is opened.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A lizard with a wide, contractile membranous frill extending from the neck and throat.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun large arboreal insectivorous Australian lizard with a ruff of skin around the neck