Pronunciation: naah-SHO-we-BEE-toe-SOR-us
Meaning: Naashoibito lizard
Author/s: Hunt and Lucas (1993)
Synonyms: None known
First Discovery: New Mexico, USA
Discovery Chart Position: #376
Naashoibitosaurus ostromi
Naashoibitosaurus was initially described as a juvenile specimen Kritosaurus by Jack Horner in 1992, around the same time Adrian Hunt and Spencer Lucas were busy assigning its remains to Edmontosaurus saskatchewanensis (mainly because they thought Kritosaurus was Gryposaurus). But when further scrutiny of its fossils revealed no discernible Edmontosaurus-like features, the latter experts were forced into a flip-flop and instead coined Naashoibitosaurus... for the area in which it wasn't found.
Messrs Hunt and Lucas believed David Gillette and David Thomas had found Naashoibitosaurus in the old Naashoibito member of the Kirtland Formation, with age difference being another reason they thought it differed from Kritosaurus. But it was actually discovered in the younger De-na-zin member, which makes the pair pretty much the same age. In 2000, Thomas Williamson sided with Horner, insisting differences in the features of its skull, sadly lacking a beak and lower jaw but with a low nasal crest that peaks in front of the eyes, were simply age-related. All later reviews concluded that Naashoibitosaurus and Kritosaurus are closely related but independent critters.
Naashoibitosaurus is a saurolophine hadrosaurid: one of the flamboyant-crest-lacking duck-billed dinosaurs known for the last five decades of the 20th century and the first of the 21st as Hadrosaurines. Whether it actually belongs to Kritosaurus or represents a distinct critter in its own right, its family ties won't change because Kritosaurus is a saurolophine hadrosaurid too.
Messrs Hunt and Lucas believed David Gillette and David Thomas had found Naashoibitosaurus in the old Naashoibito member of the Kirtland Formation, with age difference being another reason they thought it differed from Kritosaurus. But it was actually discovered in the younger De-na-zin member, which makes the pair pretty much the same age. In 2000, Thomas Williamson sided with Horner, insisting differences in the features of its skull, sadly lacking a beak and lower jaw but with a low nasal crest that peaks in front of the eyes, were simply age-related. All later reviews concluded that Naashoibitosaurus and Kritosaurus are closely related but independent critters.
Naashoibitosaurus is a saurolophine hadrosaurid: one of the flamboyant-crest-lacking duck-billed dinosaurs known for the last five decades of the 20th century and the first of the 21st as Hadrosaurines. Whether it actually belongs to Kritosaurus or represents a distinct critter in its own right, its family ties won't change because Kritosaurus is a saurolophine hadrosaurid too.
(Ostrom's Naashoibito lizard)Etymology
Naashoibitosaurus is derived from the Navajo “na'asho'i bito'i†(lizard creek) and the Greek "sauros" (lizard). It was named for the Naashoibito Member of the Kirkland Formation but it was actually found in what turned out to be the De-na-zin Member. The species epithet, ostromi, honors paleontologist John Ostrom.
Discovery
The only remains of Naashoibitosaurus were discovered at "Willow Wash" in the De-na-zin Member of the Kirtland Formation, San Juan County, New Mexico, USA.The holotype (NMMNH P-16106) is a partial skeleton.
