A 2025 paper by Lindsay Zanno and James Napoli concluded that some bones from the 'Dueling Dinosaurs' specimen represent a fully grown individual of Nanotyrannus lancensis rather than a juvenile Tyrannosaurus rex.
October 30, 2025
high
temporal
Taxonomic reinterpretation of bones from the well-known 'Dueling Dinosaurs' fossil assemblage.
The taxon name Nanotyrannus lancensis was assigned to a medium-sized theropod dinosaur in 1988.
January 01, 1988
high
taxonomy
Historical taxonomic designation for a medium-sized tyrannosaur specimen.
Nanotyrannus lancensis is described as a small-bodied, agile tyrannosauroid with relatively long legs and proportionally larger forelimbs compared with Tyrannosaurus rex.
high
taxonomic
Morphological descriptions of small tyrannosauroid taxa emphasize adaptations for speed and agility versus the larger, more robust form of T. rex.