Ankylosaurus
Ankylosaurus is a genus of armored dinosaur. Its fossils have been found in geological formations dating to the very end of the Cretaceous Period, about 70-66 million years ago, in western North America, making it among the last of the non-avian dinosaurs. It was named by Barnum Brown in 1908; it is monotypic, containing only A. magniventris. The generic name means "fused" or "bent lizard", and the specific name means "great belly". A handful of specimens have been excavated to date, but a complete skeleton has not been discovered. Though other members of Ankylosauria are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal member of its group, despite having some unusual features.

Tim Evanson · CC BY-SA 2.0 · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.
On record
Recorded, not inferred- Sits inside
- AnkylosaurinaePBDB
- Diet
- herbivorePBDB, for Ornithischia
- Life habit
- ground dwelling, gregariousPBDB, for Ornithischia
- Motility
- actively mobilePBDB, for Ornithischia
- Environment
- terrestrialPBDB, for Ornithischia
- Length
- 8 mWikidata
- Mass
- 6 tonneWikidata
Time the record covers
At most 18 million years on record.
Every occurrence read is dated to somewhere between 83.6 Mya and 66 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.
16 occurrences of Ankylosaurus on record, most of them in the Late Cretaceous. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.
When
16 occurrences- Late Cretaceous100%
These are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.
Found in
6 formations
- Ferris Formation5
- Hell Creek Formation · Montana Group4
- Lance Formation3
- Scollard Formation · Edmonton Group2
- Kirtland Formation1
- Frenchman Formation1
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The named rock units Ankylosaurus has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Ankylosaurus and its relatives
Late CretaceousWhere Ankylosaurus and its relatives were recorded in the Late Cretaceous.
Found in the same rock
222 taxa- Theropoda7 sites
- Cyclurus fragosus6 sites
- Lepisosteidae5 sites
- Trionychidae5 sites
- Basilemys4 sites
- Borealosuchus sternbergii4 sites
- Brachychampsa4 sites
- Cimolodon nitidus4 sites
- Habrosaurus dilatus4 sites
- Lonchidion selachos4 sites
- Myledaphus bipartitus4 sites
- Paronychodon4 sites
- Adocus3 sites
- Baenidae3 sites
- Brachychampsa montana3 sites
- Chamops segnis3 sites
- Champsosaurus3 sites
- Chasmosaurinae3 sites
- Lepisosteus occidentalis3 sites
- Meniscoessus robustus3 sites
- Mesodma thompsoni3 sites
- Odaxosaurus piger3 sites
- Opisthotriton kayi3 sites
- Pachycephalosaurus wyomingensis3 sites
The Paleobiology Database records 16 sites for Ankylosaurus, and this reads all of them. The number is how many of those sites it was catalogued from too. The 24 sharing the most are listed.
This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.
Entered from
9 references- Unusual cranial and postcranial anatomy in the archetypal ankylosaur Ankylosaurus magniventris5
- Redescription of Ankylosaurus magniventris Brown 1908 (Ankylosauridae) from the Upper Cretaceous of the Western Interior of North America3
- Baby dinosaurs from the Late Cretaceous Lance and Hell Creek formations and a description of a new species of theropod2
- The paleontology, geology and taphonomy of the Tooth Draw Deposit; Hell Creek Formation (Maastrictian), Butte County, South Dakota1
- Systematics, phylogeny and palaeobiogeography of the ankylosaurid dinosaurs1
- Paleontology and paleoecology of the Lance Formation (Maastrichtian), east flank of Rock Springs Uplift, Sweetwater County, Wyoming1
- Paleontological survey, resource assessment, and mitigation plan for the Bisti-Star Lake Area, northwestern New Mexico1
- Cretaceous Eocene correlation in New Mexico, Wyoming, Montana, Alberta1
- The Ankylosauridae, a new family of armored dinosaurs from the Upper Cretaceous1
Each of the 16 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content2
Picture of Ankylosaurus
- Source
- Wikipedia/Commons
- Credit
- Tim Evanson
- Licence
- CC BY-SA 2.0
- Commercial use
- the licence allows it
Smithsonian Open Access and MorphoSource were not reached for this taxon, so this list is what the others held rather than everything there is.
The description on this site
- Licence
- CC BY-SA 4.0
This is what the site found, which is not the same as what exists.
Keep going
What may have been alongside itAnkylosaurinae through timeFormations of the Late CretaceousThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Brown 1908