Data from: The dentary of Wareolestes rex (Megazostrodontidae): a new specimen from Scotland and implications for morganucodontan tooth replacement

The Middle Jurassic morganucodontan, Wareolestes rex, was previously known
from only four isolated molars from Kirtlington, England. There has been
debate over the position of the holotype tooth as an upper or lower molar.
We describe a new Wareolestes specimen from the Kilmaluag Formation of
Scotland: a partial left dentary with two erupted molars, one unerupted
molar and three unerupted premolars. Empty alveoli for a canine, p1 and p3
are also present. Through detailed comparison of the morphology of the
holotype and our new material, we support the original diagnosis of the
holotype Wareolestes as a lower molar, most likely m1. The position of
erupted and unerupted replacement teeth in the newly discovered specimen
supports a diphyodont pattern of tooth replacement of premolariform
dentition in Wareolestes, as suggested for other morganucodontans such as
Morganucodon, Megazostrodon and Dinnetherium. However, damage to the
dentary means that questions remain regarding the sequence of replacement
in Wareolestes along the tooth row.