# 1903 in paleontology

Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1903.

## Dinosaurs
### New taxa

| Taxon | Novelty | Status | Author(s) | Age | Unit | Location | Notes |
| Brachiosaurus | Gen. et sp. nov. | Valid | Riggs | Late Jurassic | Morrison Formation | Colorado | A brachiosaurid |
| Claosaurus affinis | Sp. nov. | Nomen dubium | Wieland | Maastrichtian | Pierre Shale | South Dakota | A species of Claosaurus |
| Haplocanthosaurus | Gen. nov. | Nomen conservandum | Hatcher | Late Jurassic | Morrison Formation | Colorado | New name for "Haplocanthus", mistakenly thought preoccupied |
| Haplocanthosaurus utterbacki | Sp. nov. | Jr. synonym | Hatcher | Late Jurassic | Morrison Formation | Colorado | A species of Haplocanthosaurus now a synonym of Haplocanthosaurus priscus |
| Haplocanthus priscus | Gen. et sp. nov. | Nomen rejectum | Hatcher | Late Jurassic | Morrison Formation | Colorado | Erroneously thought preoccupied by Haplacanthus Agassiz, 1845 and renamed Haplocanthosaurus. |
| Ornitholestes | Gen. et sp. nov. | Valid | Osborn | Kimmeridgian | Morrison Formation | Wyoming | Known from a single skull and partial skeleton. |
| Telmatosaurus | Gen. nov. | Valid | Nopcsa | Maastrichtian | Sânpetru Formation | Romania | New genus name for Limnosaurus transsylvanicus |

## Sauropterygians

* Plesiosaur gastroliths documented.

### Newly named plesiosaurs

| Name | Novelty | Status | Authors | Age | Unit | Location | Notes | Images |
| Apatomerus | gen et sp | Valid | Williston | Albian | Kiowa Shale, Kansas | | first described as a pterosaur; reidentified in the 1970s | |
| Brachauchenius | gen et sp | Valid | Williston | Turonian | Greenhorn Formation, | Colombia  UK  USA ( Colorado, Kansas, Texas and Utah) | A brachauchenine pliosaurid. | Brachauchenius lucasi pursuing a generic hesperornithiform bird. |
| Dolichorhynchops | gen et sp | Valid | Williston | Turonian | Smoky Hill Chalk, Kansas | Canada ( Manitoba, Northwest Territories and Saskatchewan)  USA ( Kansas, South Dakota, Texas, Utah and Wyoming) | A polycotylid. | |

## Synapsids
### Non-mammalian

| Name | Novelty | Status | Authors | Age | Unit | Location | Images |
| Lycosuchus | gen et sp | Valid | Broom | Middle Permian | Middle Abrahamskraal Formation | South Africa | Lycosuchus |
| Scylacosaurus | gen et sp | Valid | Broom | Late Permian | Cistecephalus Assemblage Zone | South Africa | Scylacosaurus |
| Scymnosaurus | gen et sp | Valid | Broom | Middle Permian | Middle Abrahamskraal Formation | South Africa | |

### Eutherians
#### Cetaceans

| Name | Novelty | Status | Authors | Age | Unit | Location | Notes | Images |
| Squalodon bariensis latirostris | Ssp. nov | Valid | Capellini | Late Oligocene (Chattian) | Unnamed deposit | Italy | A squalodontid; now recognized as a species of Eosqualodon. | |
Pholidotes
| Name | Authors | Age | Location | Notes | Images |
| Metacheiromys | Wortman | 48 Million years ago. | USA ( Colorado and Wyoming) | An Eocene Mammal related to modern pangolins. | Metacheiromys |