Ellesmeroceras

Ellesmeroceras is the type genus for the Ellesmeroceratidae, a family of primitive nautiloid cephalopods, that is characterized by its small, generally compressed, gradually expanded, orthoconic shell, found in Lower Ordovician marine sediments. The septa are close spaced and the siphuncle is ventral, about 0.2 the diameter of the shell. Septal necks are typically orthochoanitic but may slant inwardly (loxochoanitic) or reach halfway to the previous septum (hemichoanitic). Connecting rings are thick. As common for the Ellesmerocerida, Ellesmeroceras has diaphragms within the siphuncle tube.

Ellesmeroceras

Apokryltaros · 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
EllesmeroceratidaePBDB
Diet
carnivorePBDB, for Cephalopoda
Life habit
nektobenthic, solitaryPBDB, for Ellesmerocerida
Motility
actively mobilePBDB, for Ellesmerocerida
Vision
well-developedPBDB, for Cephalopoda
Environment
marinePBDB, for Ellesmerocerida

Time the record covers

At least 6.3 million years on record.

The record covers at least 483.4 Mya to 477.1 Mya. No occurrence read is dated outside 488.9 Mya to 457.3 Mya.

Cambrian — about 1 of 30 occurrencesOrdovician — about 29 of 30 occurrencesOrdovician490–488 Mya — about 0.3 occurrences488–487 Mya — about 0.6 occurrences487–486 Mya — about 2 occurrences486–485 Mya — about 3 occurrences485–484 Mya — about 3 occurrences484–483 Mya — about 3 occurrences483–482 Mya — about 3 occurrences482–481 Mya — about 2 occurrences481–480 Mya — about 2 occurrences480–479 Mya — about 2 occurrences479–477 Mya — about 2 occurrences477–476 Mya — about 1 occurrence476–475 Mya — about 0.6 occurrences475–474 Mya — about 0.6 occurrences474–473 Mya — about 0.6 occurrences473–472 Mya — about 0.6 occurrences472–471 Mya — about 0.5 occurrences471–470 Mya — about 0.4 occurrences470–469 Mya — about 0.4 occurrences469–468 Mya — about 0.3 occurrences468–467 Mya — about 0.0 occurrences467–465 Mya — about 0.0 occurrences465–464 Mya — about 0.0 occurrences464–463 Mya — about 0.0 occurrences463–462 Mya — about 0.0 occurrences462–461 Mya — about 0.0 occurrences461–460 Mya — about 0.0 occurrences460–459 Mya — about 0.0 occurrences459–458 Mya — about 0.0 occurrences458–457 Mya — about 0.0 occurrences483.4 Mya477.1 Mya489.5 Mya456.7 Mya

30 occurrences of Ellesmeroceras on record, most of them in the Ordovician. 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

30 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

18 formations

Great Meadows — 43.91°N, 73.42°WGreat Meadows — 43.42°N, 73.48°WYeli — 40.00°N, 118.00°EYeli — 40.00°N, 119.00°ELianjiashan — 39.00°N, 118.00°ELianjiashan — 39.00°N, 115.00°EOneota — 44.01°N, 91.46°WOneota — 43.90°N, 91.34°WOneota Dolomite — 43.02°N, 91.18°WSailmhor — 58.24°N, 4.18°WSailmhor — 58.57°N, 4.71°WStonehenge Limestone — 39.63°N, 77.82°WPanjiazui — 29.00°N, 111.00°ELunshan — 32.00°N, 118.00°EYinshan — 41.00°N, 79.00°EWan-wan-kou — 38.35°N, 125.43°ELiuxia — 30.25°N, 119.92°EUst'kut — 67.37°N, 104.07°ETribes Hill — 42.90°N, 74.56°WSierrite — 33.16°N, 107.30°WTanyard — 30.46°N, 99.13°WGasconade — 37.59°N, 90.17°WKochakan — 67.53°N, 104.18°E

Loading coastlines…

The named rock units Ellesmeroceras has been recovered from, largest first. Drawn where the rock is now, not where it formed. 4 occurrences have no formation on record, which is common for older literature.

Ellesmeroceras and its relatives

Ordovician

Where Ellesmeroceras and its relatives were recorded in the Ordovician.

Found in the same rock

220 taxa

The Paleobiology Database records 28 sites for Ellesmeroceras, 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

16 references

Each of the 30 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. 4 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 content1

Picture of Ellesmeroceras

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

No 3D scan of Ellesmeroceras 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 itEllesmeroceratidae through timeFormations of the OrdovicianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Foerste 1921