Pachyceras

Pachyceras is a genus of perisphinctoid ammonites from the Middle Jurassic, upper Callovian stage, and is the type genus for the family Pachyceratidae. The shell is involute, subglobular, with a deep umbilicus and flattened flanks that slope toward a more narrowly rounded venter, and covered by low, widely spaced ribs.

Pachyceras

Hectonichus · 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
PachyceratidaePBDB
Diet
carnivorePBDB, for Ammonoidea
Life habit
nektonicPBDB, for Ammonoidea
Motility
fast-movingPBDB, for Ammonoidea
Vision
well-developedPBDB, for Cephalopoda
Environment
marinePBDB, for Cephalopoda

Time the record covers

At least 296 million years on record.

The record covers at least 458.2 Mya to 161.5 Mya. No occurrence read is dated outside 469.4 Mya to 154.8 Mya.

Ordovician — about 2 of 27 occurrencesOrdovicianSilurian — about 5 of 27 occurrencesDevonian — about 3 of 27 occurrencesDevonianCarboniferous — about 0 of 27 occurrencesPermian — about 0 of 27 occurrencesEarly Triassic — about 0 of 27 occurrencesMiddle Triassic — about 0 of 27 occurrencesLate Triassic — about 0 of 27 occurrencesEarly Jurassic — about 0 of 27 occurrencesMiddle Jurassic — about 12 of 27 occurrencesLate Jurassic — about 5 of 27 occurrences476–465 Mya — about 0.4 occurrences465–454 Mya — about 1 occurrence454–443 Mya — about 0.6 occurrences443–432 Mya — about 5 occurrences421–410 Mya — about 3 occurrences170–159 Mya — about 16 occurrences159–149 Mya — about 1 occurrence458.2 Mya161.5 Mya476 Mya149 Mya

27 occurrences of Pachyceras on record, most of them in the Middle Jurassic. 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

27 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

7 formations

Tuwaiq Mt.Lst. — 21.62°N, 45.50°ETuwaiq Mt.Lst. — 25.57°N, 45.00°EDhruma — 26.20°N, 44.83°EDhruma — 26.33°N, 44.83°EYanwashan — 28.00°N, 118.00°EHabo beds — 23.20°N, 69.80°ETuwaiq Mountain — 25.04°N, 45.88°EMarnes de Dives — 49.32°N, 0.00°EShihtien — 24.77°N, 99.15°E

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The named rock units Pachyceras has been recovered from, largest first. Drawn where the rock is now, not where it formed. 16 occurrences have no formation on record, which is common for older literature.

Pachyceras and its relatives

Middle Jurassic

Where Pachyceras and its relatives were recorded in the Middle Jurassic.

Found in the same rock

279 taxa

The Paleobiology Database records 19 sites for Pachyceras, 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

12 references

Each of the 27 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. 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 Pachyceras

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

No 3D scan of Pachyceras 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 itPachyceratidae through timeFormations of the Middle JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Bayle 1878