Mymoorapelta

Mymoorapelta (Meaning "Shield from the Mygatt-Moore Quarry" after a combination of the names of the discoverers of the Mygatt-Moore Quarry that fossils were originally collected from, and the Greek word πέλτα, meaning "shield") is a nodosaurid ankylosaur from the Late Jurassic (Kimmeridgian-Tithonian, around 155 to 150 million years ago) Morrison Formation (Brushy Basin Member) of western Colorado and central Utah, USA. The animal is known from a single species, Mymoorapelta maysi, and few specimens are known. The most complete specimen is the holotype individual from the Mygatt-Moore Quarry, which includes , a partial , , and other bones. It was initially described by James Kirkland and Kenneth Carpenter in 1994. Along with Gargoyleosaurus, it is one of the earliest known nodosaurids.

Mymoorapelta is one of the smaller known nodosaurids, with the estimated length of the largest specimen only reaching . It had a narrow snout and almost triangular skull in dorsal view, with two large horns pointing backwards from the brow and two horns below these that pointed backwards and down on the . Five different armor types have been observed in Mymoorapelta, ranging from elongated, sharp spines on the side of the body to a giant shield composed of tiny osteoderms, called ossicles, that covered the top of the pelvis. In contrast to the club-tailed ankylosaurids, the tail bore spikes that Mymoorapelta likely used for defense.