Aletopelta coombsi was an ankylosaurian ornithischian dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 whose fossils were found in Southern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

Etymologically, the generic name is composed of the Greek

Ancient Greek

Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 terms aletes and pelte, meaning, respectively "wandering" and "shield". This genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 name was suggested by Ben Creisler because the fossil location, at the time the dinosaur died, being located on the tectonic plate containing the Peninsular Ranges Terrane, was somewhere opposite the middle of Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. This plate had thus been wandering northward, carrying the specimen with it. The specific epithet honors the vertebrate paleontologist Walter P. Coombs, Jr., for his ground-breaking work on ankylosaurs and his years of research, which have inspired many an enthusiast as well as professional paleontologist.

Fossils

Aletopelta is a medium-sized ankylosaurid, estimated to be around 6 metres (19.7 ft) long, and known from a partial skeleton

Skeleton

The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...

 (Holotype

Holotype

A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

: SDNHM 33909 (San Diego Natural History Museum

San Diego Natural History Museum

The San Diego Natural History Museum was founded in 1874 as the San Diego Society of Natural History. The present location of the museum in San Diego's Balboa Park was dedicated on January 14, 1933....

, San Diego, California). The skeleton including femora, tibia

Tibia

The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....

e, fibulae and incomplete parts of a scapula

Scapula

In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....

, humerus

Humerus

The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

, ulna

Ulna

The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...

, left and right ischium, vertebrae, ribs, partial armor

Armour (zoology)

Armour in animals is external or superficial protection against attack by predators, formed as part of the body , usually through the hardening of body tissues, outgrowths or secretions. It has therefore mostly developed in 'prey' species...

 over the pelvic girdle plus at least 60 detached armor plates and 8 teeth was found in the Late Cretaceous

Late Cretaceous

The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

 (Upper Campanian

Campanian

The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

) marine Point Loma Formation

Point Loma Formation

The Point Loma Formation is a sedimentary geological formation in Southern California. The strata date back to the Late Cretaceous. The formation is named after Point Loma, California.-Description:...

, near Carlsbad, California

Carlsbad, California

-2010:The 2010 United States Census reported that Carlsbad had a population of 105,328. The population density was 2,693.1 people per square mile . The racial makeup of Carlsbad was 87,205 White, 1,379 African American, 514 Native American, 7,460 Asian, 198 Pacific Islander, 4,189 from other...

. Apparently, the animal's bloated carcass

Carcass

Carcass may refer to:*Cadaver of a human, or carrion of an animal.*Carcass , a death metal/grindcore band*Carcass , a type of incendiary ammunition designed to be fired from a cannon, three ships of the Royal Navy...

 floated out to sea and formed a miniature reef

Reef

In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....

 environment after it sunk to the bottom.

Aletopelta is diagnosed as an ankylosaurid mainly based on the shape and arrangement of its osteoderm armor, which is closer in form to ankylosaurids than to nodosaurids.

External links

• Aletopelta at DinoData