Megalonychidae

Megalonychidae is an extinct family of sloths including the extinct Megalonyx. Megalonychids first appeared in the early Oligocene, about 35 million years (Ma) ago, in southern Argentina (Patagonia). There is, however, one possible find dating to the Eocene, about 40 Ma ago, on Seymour Island in Antarctica. They first reached North America by island-hopping across the Central American Seaway, about 9 million years ago, prior to formation of the Isthmus of Panama about 2.7 million years ago. Some megalonychid lineages increased in size as time passed. The first species of these were small and may have been partly tree-dwelling, whereas the Pliocene species were already approximately half the size of the huge Late Pleistocene Megalonyx jeffersonii from the last ice age.

Megalonychidae

The authors of the two component images are Daderot and ДиБгд , respectively. · CC0 · 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
MegatherioideaPBDB
Diet
herbivorePBDB
Life habit
ground dwellingPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Eutheria

Time the record covers

At least 20 million years on record.

The record covers at least 21 Mya to 11.7 ka. No occurrence read is dated outside 29 Mya to 0 Mya.

Oligocene — about 3 of 421 occurrencesOligoceneMiocene — about 194 of 421 occurrencesMiocenePliocene — about 44 of 421 occurrencesPliocenePleistocene — about 174 of 421 occurrencesPleistocene30–29 Mya — about 0.2 occurrences29–28 Mya — about 0.5 occurrences28–27 Mya — about 0.5 occurrences27–26 Mya — about 0.5 occurrences26–25 Mya — about 0.5 occurrences25–24 Mya — about 0.5 occurrences24–23 Mya — about 0.6 occurrences23–22 Mya — about 0.7 occurrences22–21 Mya — about 0.9 occurrences21–20 Mya — about 2 occurrences20–19 Mya — about 2 occurrences19–18 Mya — about 2 occurrences18–17 Mya — about 49 occurrences17–16 Mya — about 31 occurrences16–15 Mya — about 0.2 occurrences15–14 Mya — about 0.2 occurrences14–13 Mya — about 12 occurrences13–12 Mya — about 12 occurrences12–11 Mya — about 12 occurrences11–9.9 Mya — about 2 occurrences9.9–8.9 Mya — about 7 occurrences8.9–7.9 Mya — about 12 occurrences7.9–6.9 Mya — about 18 occurrences6.9–5.9 Mya — about 19 occurrences5.9–4.9 Mya — about 18 occurrences4.9–3.9 Mya — about 13 occurrences3.9–3.0 Mya — about 18 occurrences3.0–2.0 Mya — about 25 occurrences2.0–986 ka Mya — about 34 occurrences986 ka–0 Mya — about 128 occurrences21 Mya11.7 ka29.6 Mya0 Mya

421 occurrences of Megalonychidae on record, most of them in the Miocene. The Paleobiology Database records this as a living group. 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

421 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

83 formations

Santa Cruz — 51.02°S, 69.15°WSanta Cruz — 51.20°S, 69.12°WSanta Cruz — 50.16°S, 69.67°WSanta Cruz — 50.27°S, 70.37°WSanta Cruz — 50.25°S, 71.07°WSanta Cruz — 51.57°S, 69.47°WSanta Cruz — 51.60°S, 69.56°WSanta Cruz — 51.57°S, 69.42°WSanta Cruz — 47.50°S, 71.88°WSanta Cruz — 50.00°S, 70.00°WSanta Cruz — 50.60°S, 69.08°WSanta Cruz — 50.32°S, 68.90°WSanta Cruz — 50.75°S, 69.18°WSanta Cruz — 51.34°S, 69.02°WSanta Cruz — 51.35°S, 69.00°WSanta Cruz — 50.32°S, 72.10°WSanta Cruz — 47.58°S, 71.85°WSanta Cruz — 50.28°S, 70.28°WLa Victoria — 3.27°N, 75.19°WLa Victoria — 3.34°N, 75.15°WLa Victoria — 3.36°N, 75.16°WLa Victoria — 3.23°N, 75.11°WItuzaingo — 31.48°S, 60.23°WItuzaingo — 31.70°S, 60.48°WItuzaingo — 31.63°S, 60.33°WVillavieja — 3.78°N, 75.18°WVillavieja — 3.26°N, 75.18°WVillavieja — 3.24°N, 75.18°WVillavieja — 3.22°N, 75.14°WVillavieja — 3.21°N, 75.26°WPalm Spring — 32.90°N, 117.10°WSnake Creek — 42.40°N, 103.80°WAsh Hollow — 42.70°N, 100.00°WAsh Hollow — 40.50°N, 100.50°WAsh Hollow — 41.30°N, 101.89°WAsh Hollow — 41.40°N, 102.40°WSolimoes — 10.12°S, 66.88°WSarmiento — 45.67°S, 68.71°WSan Timoteo — 33.90°N, 117.00°WTamiami — 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°WPalos Verdes Sand — 34.00°N, 118.20°WPalos Verdes Sand — 33.60°N, 117.80°WOgallala — 36.70°N, 101.40°WOgallala — 37.20°N, 99.90°WAlachua — 29.65°N, 82.60°WAlachua — 29.10°N, 82.30°WChamita — 36.50°N, 107.00°WMehrten — 37.30°N, 120.60°WMehrten — 37.60°N, 120.80°WCaliente — 35.10°N, 120.00°WCaliente — 35.30°N, 118.50°WGila Conglomerate — 32.90°N, 109.10°WGila Conglomerate — 32.70°N, 109.00°WRexroad — 37.20°N, 100.30°WCrooked Creek — 37.20°N, 100.30°WRingold — 47.00°N, 118.50°WRingold — 46.30°N, 119.10°WCuscatlán — 13.75°N, 88.83°WMcPherson — 38.30°N, 97.60°W

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The named rock units Megalonychidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 59 further formations hold fewer occurrences each and are not listed. 174 occurrences have no formation on record, which is common for older literature.

Megalonychidae and its relatives

Miocene

Where Megalonychidae and its relatives were recorded in the Miocene.

Found in the same rock

2,372 taxa

The Paleobiology Database records 312 sites for Megalonychidae, and this reads 240 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

205 references

Each of the 421 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. 193 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 Megalonychidae

Credit
The authors of the two component images are Daderot and ДиБгд , respectively.
Licence
CC0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
Commercial use
the licence does not allow it

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 itMegatherioidea through timeFormations of the MioceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Gervais 1855