Thalassocnus

Thalassocnus is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—T. antiquus, T. natans, T. littoralis, T. carolomartini, and T. yuacensis—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths, but they may have also been adapted to a terrestrial lifestyle. They have been found in the Pisco Formation of Peru, the Tafna Formation of Argentina, and the Bahía Inglesa, Coquimbo, and Horcón formations of Chile. Thalassocninae has been placed in both the families Megatheriidae and Nothrotheriidae.

Thalassocnus

FunkMonk · CC BY-SA 3.0 · 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
ThalassocninaePBDB
Diet
omnivorePBDB, for Xenarthra
Life habit
aquaticPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Eutheria

Time the record covers

At least 3.6 million years on record.

The record covers at least 7.246 Mya to 3.6 Mya. No occurrence read is dated outside 11.63 Mya to 2.58 Mya.

Miocene — about 11 of 15 occurrencesMiocenePliocene — about 4 of 15 occurrencesPliocenePleistocene — about 0 of 15 occurrences12–11 Mya — about 0.2 occurrences11–11 Mya — about 0.4 occurrences11–11 Mya — about 0.4 occurrences11–10 Mya — about 0.4 occurrences10–10 Mya — about 0.4 occurrences10–9.8 Mya — about 0.4 occurrences9.8–9.4 Mya — about 0.4 occurrences9.4–9.1 Mya — about 0.4 occurrences9.1–8.8 Mya — about 0.4 occurrences8.8–8.4 Mya — about 0.4 occurrences8.4–8.1 Mya — about 0.4 occurrences8.1–7.8 Mya — about 0.4 occurrences7.8–7.4 Mya — about 0.4 occurrences7.4–7.1 Mya — about 0.7 occurrences7.1–6.8 Mya — about 1 occurrence6.8–6.4 Mya — about 1 occurrence6.4–6.1 Mya — about 1 occurrence6.1–5.8 Mya — about 1 occurrence5.8–5.4 Mya — about 1 occurrence5.4–5.1 Mya — about 0.6 occurrences5.1–4.8 Mya — about 0.4 occurrences4.8–4.4 Mya — about 0.4 occurrences4.4–4.1 Mya — about 0.4 occurrences4.1–3.8 Mya — about 0.4 occurrences3.8–3.4 Mya — about 0.4 occurrences3.4–3.1 Mya — about 0.5 occurrences3.1–2.8 Mya — about 0.5 occurrences2.8–2.4 Mya — about 0.2 occurrences7.246 Mya3.6 Mya12.1 Mya2.1 Mya

15 occurrences of Thalassocnus on record, most of them in the Miocene. 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

15 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

4 formations

Pisco — 15.50°S, 74.80°WPisco — 15.58°S, 74.72°WPisco — 15.67°S, 74.51°WPisco — 15.55°S, 74.80°WBahía Inglesa — 27.00°S, 70.79°WBahía Inglesa — 27.08°S, 70.84°WCoquimbo — 30.00°S, 71.33°WTafna — 21.99°S, 65.88°W

Loading coastlines…

The named rock units Thalassocnus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 1 occurrence has no formation on record, which is common for older literature.

Thalassocnus and its relatives

Miocene

Where Thalassocnus and its relatives were recorded in the Miocene.

Found in the same rock

128 taxa

The Paleobiology Database records 15 sites for Thalassocnus, 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

13 references

Each of the 15 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. 1 further reference is 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 content1

Picture of Thalassocnus

Credit
FunkMonk
Licence
CC BY-SA 3.0
Commercial use
the licence allows it

No 3D scan of Thalassocnus was found in MorphoSource and Sketchfab.

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

Occurrence data from the Paleobiology Database, CC BY 4.0. Muizon and McDonald 1995