Megalonyx leptostomus

Megalonyx is an extinct genus of ground sloths of the family Megalonychidae, native to North America. It evolved during the Pliocene Epoch and became extinct at the end of the Late Pleistocene, living from ~5 million to ~13,000 years ago. The type species, M. jeffersonii, the youngest and largest known species, measured about 3 m (9.8 ft) in length and weighed up to nearly 1,300 kg (2,900 lb).

Megalonyx leptostomus

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
MegalonyxPBDB
Diet
herbivorePBDB, for Megalonychidae
Life habit
ground dwellingPBDB, for Megalonychidae
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Eutheria

Time the record covers

At least 400 thousand years on record.

The record covers at least 1.8 Mya to 1.4 Mya. No occurrence read is dated outside 4.7 Mya to 210 ka.

Pliocene — about 10 of 22 occurrencesPliocenePleistocene — about 12 of 22 occurrencesPleistoceneHolocene — about 0 of 22 occurrences4.9–4.7 Mya — about 0.1 occurrences4.7–4.5 Mya — about 0.8 occurrences4.5–4.3 Mya — about 0.8 occurrences4.3–4.2 Mya — about 0.8 occurrences4.2–4.0 Mya — about 0.8 occurrences4.0–3.8 Mya — about 0.8 occurrences3.8–3.6 Mya — about 0.8 occurrences3.6–3.5 Mya — about 0.8 occurrences3.5–3.3 Mya — about 0.8 occurrences3.3–3.1 Mya — about 0.8 occurrences3.1–2.9 Mya — about 0.8 occurrences2.9–2.8 Mya — about 0.8 occurrences2.8–2.6 Mya — about 0.8 occurrences2.6–2.4 Mya — about 1 occurrence2.4–2.3 Mya — about 2 occurrences2.3–2.1 Mya — about 2 occurrences2.1–1.9 Mya — about 2 occurrences1.9–1.7 Mya — about 1 occurrence1.7–1.6 Mya — about 1 occurrence1.6–1.4 Mya — about 1 occurrence1.4–1.2 Mya — about 0.5 occurrences1.2–1.0 Mya — about 0.5 occurrences1.0–867 ka Mya — about 0.5 occurrences867 ka–693 ka Mya — about 0.3 occurrences693 ka–520 ka Mya — about 0.2 occurrences520 ka–347 ka Mya — about 0.2 occurrences347 ka–173 ka Mya — about 0.1 occurrences1.8 Mya – 1.4 Mya5.2 Mya0 Mya

22 occurrences of Megalonyx leptostomus on record, most of them in the Pleistocene. 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

22 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

9 formations

Tamiami — 27.37°N, 82.45°WTamiami — 27.30°N, 80.80°WTamiami — 27.78°N, 82.68°WBlanco — 33.81°N, 101.21°WBlanco — 33.70°N, 101.10°WRingold — 47.00°N, 118.50°WRingold — 46.30°N, 119.10°WGila Conglomerate — 32.70°N, 109.00°WRexroad — 37.20°N, 100.30°WPalomas — 34.00°N, 107.00°WBon Homme Gravel — 43.00°N, 97.40°WCaloosahatchee — 27.04°N, 81.82°WWaccamaw — 33.00°N, 80.18°W

Loading coastlines…

The named rock units Megalonyx leptostomus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 9 occurrences have no formation on record, which is common for older literature.

Megalonyx leptostomus and its relatives

Pleistocene

Where Megalonyx leptostomus and its relatives were recorded in the Pleistocene.

Found in the same rock

377 taxa

The Paleobiology Database records 22 sites for Megalonyx leptostomus, 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

18 references

Each of the 22 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. 6 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 content2

Picture of Megalonyx leptostomus

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

Laser scan

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
Megalonyx leptostomus · UF:VP:52375

Smithsonian Open Access was 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 itMegalonyx through timeFormations of the PleistoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Cope 1893