Grammoceras

Grammoceras is an extinct genus of ammonite found in Yorks Ravenscar, England, from Jurassic period sediments. Its overall distribution is fairly worldwide.

Grammoceras

via iDigBio · CC0 · via iDigBio. 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
GrammoceratinaePBDB
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 18 million years on record.

The record covers at least 192.9 Mya to 174.7 Mya. No occurrence read is dated outside 199.5 Mya to 170.9 Mya.

Early Jurassic — about 85 of 91 occurrencesEarly JurassicMiddle Jurassic — about 6 of 91 occurrencesMiddle Jurassic200–199 Mya — about 0.1 occurrences199–198 Mya — about 0.1 occurrences198–197 Mya — about 0.1 occurrences197–196 Mya — about 0.1 occurrences196–195 Mya — about 0.1 occurrences195–194 Mya — about 0.1 occurrences194–193 Mya — about 0.1 occurrences193–192 Mya — about 0.0 occurrences184–183 Mya — about 1 occurrence183–182 Mya — about 2 occurrences182–181 Mya — about 2 occurrences181–180 Mya — about 4 occurrences180–179 Mya — about 14 occurrences179–178 Mya — about 14 occurrences178–177 Mya — about 14 occurrences177–176 Mya — about 14 occurrences176–175 Mya — about 14 occurrences175–174 Mya — about 9 occurrences174–173 Mya — about 2 occurrences173–172 Mya — about 2 occurrences172–171 Mya — about 2 occurrences171–170 Mya — about 0.7 occurrences192.9 Mya174.7 Mya200.1 Mya170.3 Mya

91 occurrences of Grammoceras 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

91 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

12 formations

Whiteaves — 53.42°N, 132.27°WBraunjura alpha & Braunjura beta — 48.90°N, 7.67°EKisgerecse — 47.70°N, 18.47°EDogger — 54.41°N, 0.93°WJurensismergel — 49.91°N, 11.46°EJurensismergel — 47.95°N, 7.82°EJurensismergel — 48.83°N, 10.10°EMarnes de Fontaneilles — 43.85°N, 3.12°ELautaro — 29.01°S, 70.20°WLautaro — 29.36°S, 70.19°WTolgyhat Limestone — 47.70°N, 18.49°EKisgerecse Marl — 47.70°N, 18.49°EOzirovo — 43.03°N, 23.25°EAgardhfjellet — 78.17°N, 18.87°EAdnet — 48.89°N, 19.08°E

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The named rock units Grammoceras has been recovered from, largest first. Drawn where the rock is now, not where it formed. 45 occurrences have no formation on record, which is common for older literature.

Grammoceras and its relatives

Early Jurassic

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

Found in the same rock

207 taxa

The Paleobiology Database records 69 sites for Grammoceras, 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

22 references

Each of the 91 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. 10 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 content2

Picture of Grammoceras

Source
iDigBio
Credit
via iDigBio
Licence
CC0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
Commercial use
the licence does not allow it

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

What may have been alongside itGrammoceratinae through timeFormations of the Early JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.