Pronunciation: EE-o-BRON-to-SOR-us
Meaning: Dawn Thunder Lizard
Author/s: Bakker (1998)
Synonyms: Apatosaurus yahnahpin
First Discovery: Wyoming, USA
Discovery Chart Position: #
Eobrontosaurus yahnahpin
As payback on behalf of a much-loved dinosaur called Brontosaurus that was sunk as a synonym of Apatosaurus way back in 1903, Eobrontosaurus (dawn Brontosaurus), first described in 1994 as Apatosaurus yahnahpin by James Filla and Patrick Redman who affectionately referred to it as "Bertha", turned the tables. A re-evaluation of its remains by Bob Bakker, who took the loss of Brontosaurus particularly badly, found them to belong to a critter more primitive than Apatosaurus, possibly directly ancestral, and he honoured Brontosaurus when he coined the new generic name in 1998.
In 2004, rumours began to circulate that Eobrontosaurus was "probably" synonymous with Camarasaurus based on nothing more than the words and figures from the original description. A trip to Glen Rock to re-analyse the actual physical remains revealed that the "long neck rib", which would've excluded it from Diplodocidae, was actually a fragmentary ilium (hip bone) and not only is Eobrontosaurus yahnahpin a bonafide apatosaurine diplodocid but its species epithet (see etymology) is a misnomer.
Coming full circle, Emanuel Tschopp resurrected the original Brontosaurus as a valid critter in 2015 and raised two more species of it. Unfortunately, one of them is Brontosaurus yahnahpin. Recognize the epithet? Yup, Brontosaurus mercilessly snaffled the remains of the critter that Bakker had named in its honour, so Eobrontosaurus yahnahpin is no more.
In 2004, rumours began to circulate that Eobrontosaurus was "probably" synonymous with Camarasaurus based on nothing more than the words and figures from the original description. A trip to Glen Rock to re-analyse the actual physical remains revealed that the "long neck rib", which would've excluded it from Diplodocidae, was actually a fragmentary ilium (hip bone) and not only is Eobrontosaurus yahnahpin a bonafide apatosaurine diplodocid but its species epithet (see etymology) is a misnomer.
Coming full circle, Emanuel Tschopp resurrected the original Brontosaurus as a valid critter in 2015 and raised two more species of it. Unfortunately, one of them is Brontosaurus yahnahpin. Recognize the epithet? Yup, Brontosaurus mercilessly snaffled the remains of the critter that Bakker had named in its honour, so Eobrontosaurus yahnahpin is no more.
Etymology
Eobrontosaurus is derived from the Greek "eos" (dawn), "bronte" (thunder) and "sauros" lizard), named for Brontosaurus, the "Thunder Lizard".
The species epithet, yahnahpin (pronounced wah-nah-pee), is derived from "mah-koo yah-nah-pin", which means "breast necklace" in the language of the Lakota Sioux who lived in the area where the fossils were found. The breast necklace is actually a series of hair pipes worn by the tribe that authors Filla and Redman thought resembled this critter's paired belly ribs.
Discovery
Affectionately called "Bertha", the Eobrontosaurus holotype (TATE-001) is a relatively complete but skulless skeleton discovered at Bertha Quarry in the Brushy Basin Member of the Morrison Formation, Como Bluff, Albany County, Wyoming, by William Harlow Reed. A skull from the Tate Museum's "Nail" Quarry may (but probably doesn't) belong here.
