Arktocara yakataga

Arktocara is an extinct genus of river dolphin from the Oligocene epoch of Alaska, containing one species, A. yakataga. Having been discovered in 25-million-year-old strata near the 60th parallel north, it is perhaps the oldest-known crown of the toothed whales and the northmost river dolphin discovered. It was a member of the now-extinct family Allodelphinidae, along with the genera Allodelphis, Goedertius, Ninjadelphis, and Zarhinocetus. It measured approximately 2.26 or 2.28 meters, comparable to its closest living relative, the South Asian river dolphin, which measures 2.4 meters (7.9 ft). However, the animal probably had an elongated beak and neck, so it may have been longer. The animal is known only from a partially preserved skull. Its ecology may have been similar to the modern-day Dall's porpoise, and it may have competed with contemporaneous delphinoids. Its remains were found in the Poul Creek Formation, which has also yielded several mollusk species.

Arktocara yakataga

Uncredited · 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
ArktocaraPBDB
Diet
carnivorePBDB, for Odontoceti
Life habit
aquatic, depth=surfacePBDB, for Cetacea
Motility
actively mobilePBDB, for Cetacea
Environment
marine,freshwaterPBDB, for Odontoceti

Time the record covers

At most 4.3 million years on record.

The one occurrence read is dated to somewhere between 27.3 Mya and 23.04 Mya, which is a dating window rather than a span.

Oligocene — about 1 of 1 occurrenceOligoceneMiocene — about 0 of 1 occurrence27–27 Mya — about 0.0 occurrences27–27 Mya — about 0.0 occurrences27–27 Mya — about 0.0 occurrences27–27 Mya — about 0.0 occurrences27–27 Mya — about 0.0 occurrences27–26 Mya — about 0.0 occurrences26–26 Mya — about 0.0 occurrences26–26 Mya — about 0.0 occurrences26–26 Mya — about 0.0 occurrences26–26 Mya — about 0.0 occurrences26–26 Mya — about 0.0 occurrences26–25 Mya — about 0.0 occurrences25–25 Mya — about 0.0 occurrences25–25 Mya — about 0.0 occurrences25–25 Mya — about 0.0 occurrences25–25 Mya — about 0.0 occurrences25–24 Mya — about 0.0 occurrences24–24 Mya — about 0.0 occurrences24–24 Mya — about 0.0 occurrences24–24 Mya — about 0.0 occurrences24–24 Mya — about 0.0 occurrences24–24 Mya — about 0.0 occurrences24–23 Mya — about 0.0 occurrences23–23 Mya — about 0.0 occurrences23–23 Mya — about 0.0 occurrences23–23 Mya — about 0.0 occurrences27.8 Mya22.5 Mya

1 occurrence of Arktocara yakataga on record, most of them in the Oligocene. 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

1 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

1 formation

Poul Creek — 60.05°N, 142.05°W

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The named rock units Arktocara yakataga has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Arktocara yakataga and its relatives

Oligocene

Where Arktocara yakataga and its relatives were recorded in the Oligocene.

Found in the same rock

2 taxa

The Paleobiology Database records 1 site for Arktocara yakataga, and this reads all of them. The number is how many of those sites it was catalogued from too.

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

1 reference

Each of the 1 occurrence 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. Each entry links to doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content1

Picture of Arktocara yakataga

Credit
nobody named on the record
Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record

No 3D scan of Arktocara yakataga was found in Sketchfab.

Smithsonian Open Access and MorphoSource were 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 itArktocara through timeFormations of the OligoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Boersma and Pyenson 2016