Hesperornis fossil map
Where fossils of Hesperornis have been found, shown on the Earth as it looked about 75 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 75 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Prehistoric birds |
|---|---|
| Lived | 89.8–66 million years ago (Coniacian to Maastrichtian) |
| Periods | Cretaceous |
| Family | Hesperornithidae |
| Named by | Marsh 1872 |
| Fossil records | 65 occurrences at 28 locations (PBDB) |
| Found in | Canada, United States, Russian Federation, Sweden |
| Rock formations | Pierre Shale, txn:39248, Rybushka, Niobrara, Kanguk, Smoking Hills |
About Hesperornis
Hesperornis (from Ancient Greek ἕσπερος (hésperos), meaning "western", and ὄρνις (órnis), meaning "bird") is a genus of cormorant-like ornithuran that spanned throughout the Campanian age, and possibly even up to the early Maastrichtian age, of the Late Cretaceous period. One of the lesser-known discoveries of the paleontologist O. C. Marsh in the late 19th century Bone Wars, it was an early find in the history of avian paleontology. Locations for Hesperornis fossils include the Late Cretaceous marine limestones from Kansas and the marine shales from Canada. Nine species are recognised, eight of which have been recovered from rocks in North America and one from Russia.
Text in “About” is quoted from the Wikipedia article Hesperornis (revision 1354542412), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q733644.
