Pronunciation: ACK-rho-THO-luhs Meaning: High dome Author/s: Evans et al. (2013) Synonyms: None known First Discovery: Alberta, Canada Chart Position: 664
When University of Toronto graduate student Caleb Brown passed paleontologist David C. Evans a lump of fossilized bone about the size of a baked potato in 2008 he knew he held in his hands a skull cap from the oldest known pachycephalosaur - or herbivorous "headbanger" - from Alberta, if not the world. Fossils of critters less than 100kg or so are generally too small to survive the ravages of badland elements and Old Father Time, heck this bone only survived because it was a good two inches thick and rock solid, but a complete lack of any other remains didn't curb the author's enthusiasm and, using a like for like downscale based on larger and more complete members of the family, they reckon Acrotholus may have been about the size of a decent-sized dog.
(Roy Audet's high dome) EtymologyAcrotholus is derived from the Greek "akros" (high) and "tholus" (dome).
The species epithet, audeti (aw-DET-eye), honors Canadian rancher Roy Audet, on whose land the fossil was dug up.
DiscoveryThe remains of Acrotholus were discovered in the Milk River Formation in the badlands of Alberta, Canada, by Caleb Brown in 2008.
The holotype (TMP - Royal Tyrrell Museum of Palaeontology - 2008.045.0001) is a domed skull roof.