Arnioceras

Searched as Arnioceras aff. speciusum. The Paleobiology Database treats Arnioceras as the accepted name.

Arnioceras is an extinct genus of large, evolute, discoidal ammonite from the Lower Jurassic. The shell is normally coiled so that all whorls are exposed. Sides bear strong sharp ribs that are straight until reaching the ventrolateral edge where they swing forward and fade. The rim (venter) is keeled and free of grooves.

Arnioceras

Daderot · 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
ArietitinaePBDB
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 most 6.6 million years on record.

The one occurrence read is dated to somewhere between 199.5 Mya and 192.9 Mya, which is a dating window rather than a span.

Early Jurassic — about 1 of 1 occurrenceEarly Jurassic200–199 Mya — about 0.0 occurrences199–199 Mya — about 0.0 occurrences199–199 Mya — about 0.0 occurrences199–199 Mya — about 0.0 occurrences199–198 Mya — about 0.0 occurrences198–198 Mya — about 0.0 occurrences198–198 Mya — about 0.0 occurrences198–198 Mya — about 0.0 occurrences198–197 Mya — about 0.0 occurrences197–197 Mya — about 0.0 occurrences197–197 Mya — about 0.0 occurrences197–197 Mya — about 0.0 occurrences197–196 Mya — about 0.0 occurrences196–196 Mya — about 0.0 occurrences196–196 Mya — about 0.0 occurrences196–196 Mya — about 0.0 occurrences196–195 Mya — about 0.0 occurrences195–195 Mya — about 0.0 occurrences195–195 Mya — about 0.0 occurrences195–195 Mya — about 0.0 occurrences195–194 Mya — about 0.0 occurrences194–194 Mya — about 0.0 occurrences194–194 Mya — about 0.0 occurrences194–194 Mya — about 0.0 occurrences194–193 Mya — about 0.0 occurrences193–193 Mya — about 0.0 occurrences193–193 Mya — about 0.0 occurrences193–193 Mya — about 0.0 occurrences200 Mya192.4 Mya

1 occurrence of Arnioceras on record, most of them in the Early 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

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

Ain Ouarka — 32.71°N, 0.16°W

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

Arnioceras and its relatives

Early Jurassic

Where Arnioceras and its relatives were recorded in the Early Jurassic.

Found in the same rock

397 taxa

The Paleobiology Database records 99 sites for Arnioceras, 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

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 Arnioceras

Credit
Daderot
Licence
CC0
Commercial use
the licence allows it

No 3D scan of Arnioceras 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 itArietitinae through timeFormations of the Early JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Hyatt 1867