Hyracotherium

Hyracotherium is an extinct genus of small perissodactyl ungulates that was found in the London Clay formation. This small, fox-sized animal was once considered to be the earliest known member of Equidae before the type species, H. leporinum, was reclassified as a palaeothere. The remaining species are now thought to belong to different genera, such as Eohippus, which had previously been synonymised with Hyracotherium.

Hyracotherium

Jonathan Chen · CC BY-SA 4.0 · 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
PalaeotheriidaePBDB
Diet
frugivore, folivorePBDB, for Palaeotheriidae
Life habit
ground dwellingPBDB, for Palaeotheriidae
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Palaeotheriidae

Time the record covers

At most 11 million years on record.

Every occurrence read is dated to somewhere between 56 Mya and 45.9 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Paleocene — about 0 of 203 occurrencesEocene — about 203 of 203 occurrencesEocene56–56 Mya — about 9 occurrences56–55 Mya — about 14 occurrences55–55 Mya — about 14 occurrences55–55 Mya — about 14 occurrences55–54 Mya — about 14 occurrences54–54 Mya — about 14 occurrences54–54 Mya — about 14 occurrences54–53 Mya — about 14 occurrences53–53 Mya — about 14 occurrences53–52 Mya — about 14 occurrences52–52 Mya — about 14 occurrences52–52 Mya — about 14 occurrences52–51 Mya — about 14 occurrences51–51 Mya — about 9 occurrences51–51 Mya — about 1 occurrence51–50 Mya — about 1 occurrence50–50 Mya — about 1 occurrence50–49 Mya — about 1 occurrence49–49 Mya — about 1 occurrence49–49 Mya — about 1 occurrence49–48 Mya — about 1 occurrence48–48 Mya — about 1 occurrence48–48 Mya — about 0.8 occurrences48–47 Mya — about 0.8 occurrences47–47 Mya — about 0.8 occurrences47–47 Mya — about 0.8 occurrences47–46 Mya — about 0.8 occurrences46–46 Mya — about 0.5 occurrences56.5 Mya45.4 Mya

203 occurrences of Hyracotherium on record, most of them in the Eocene. 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

203 occurrences

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

20 formations

DeBeque — 40.00°N, 107.90°WDeBeque — 39.20°N, 108.20°WDeBeque — 39.70°N, 107.60°WWind River — 44.00°N, 106.60°WWind River — 43.20°N, 107.10°WWind River — 43.20°N, 108.20°WWind River — 43.20°N, 107.33°WWasatch — 40.60°N, 108.10°WWasatch — 41.70°N, 109.00°WWasatch — 41.80°N, 107.00°WWasatch — 42.70°N, 110.10°WWasatch — 41.80°N, 110.70°WWasatch — 41.75°N, 108.00°WWasatch — 42.37°N, 108.91°WWillwood — 44.50°N, 108.00°WWillwood — 44.00°N, 108.00°WWillwood — 44.62°N, 108.50°WWillwood — 44.30°N, 109.00°WWillwood — 44.53°N, 108.43°WWillwood — 44.37°N, 108.67°WWillwood — 44.49°N, 108.81°WWillwood — 44.54°N, 108.63°WHuerfano — 37.80°N, 105.10°W"Wasatch" — 44.00°N, 106.60°WHannold Hill — 29.42°N, 103.14°WLower Variegated Sequence — 43.90°N, 110.80°WLower Variegated Sequence — 43.20°N, 108.20°WSan Jose — 35.70°N, 107.00°WCuchara — 37.80°N, 105.10°WWittering — 51.08°N, 1.17°WWittering — 50.94°N, 1.33°WLondon Clay — 51.35°N, 1.08°ELondon Clay — 51.40°N, 0.83°ETuscahoma — 32.36°N, 88.70°WPass Peak — 42.70°N, 110.10°WMiddle Variegated Sequence — 43.20°N, 108.20°WFarisita — 37.80°N, 105.10°WGreen River — 40.20°N, 109.90°W"Middle (?) Eocene Volcaniclastic Sequence" — 43.20°N, 107.10°WVaugirard — 48.81°N, 2.24°ELignites de Soissonais — 49.15°N, 3.92°E

Loading coastlines…

The named rock units Hyracotherium has been recovered from, largest first. Drawn where the rock is now, not where it formed. 2 occurrences have no formation on record, which is common for older literature.

Hyracotherium and its relatives

Eocene

Where Hyracotherium and its relatives were recorded in the Eocene.

Found in the same rock

714 taxa

The Paleobiology Database records 203 sites for Hyracotherium, 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

31 references

Each of the 203 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. 19 further references are not listed. 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 content3

Picture of Hyracotherium

Credit
Jonathan Chen
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

CT scan

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Hyracotherium vasacciense · MCZ:VP:VPM-19205

3D model

Source
Sketchfab
Licence
CC Attribution
Commercial use
cannot be read from the licence given — check the record

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 itPalaeotheriidae through timeFormations of the EoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Owen 1841