Tragodesmoceras

Tragodesmoceras is a large moderately involute ammonite with deeply embracing whorls that are higher than wide, a steep sided umbilicus and a narrowly rounded venter. Ornament consists of primary ribs that begin at the umbilical shoulder and smaller secondary ribs that begin mid flank. Ribs are sigmodal, periodically thickened and bent forward on the outer flank to cross the venter as chevrons. The suture has a broad trifid lateral lobe.

Tragodesmoceras

via iDigBio · CC BY · 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
MuniericeratidaePBDB
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 11 million years on record.

Every occurrence read is dated to somewhere between 100.5 Mya and 89.8 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Early Cretaceous — about 0 of 49 occurrencesLate Cretaceous — about 49 of 49 occurrencesLate Cretaceous101–100 Mya — about 0.0 occurrences100–100 Mya — about 0.1 occurrences100–99 Mya — about 0.1 occurrences99–99 Mya — about 0.1 occurrences99–99 Mya — about 0.1 occurrences99–98 Mya — about 0.1 occurrences98–98 Mya — about 0.1 occurrences98–97 Mya — about 0.1 occurrences97–97 Mya — about 0.1 occurrences97–97 Mya — about 0.1 occurrences97–96 Mya — about 0.1 occurrences96–96 Mya — about 0.1 occurrences96–96 Mya — about 0.1 occurrences96–95 Mya — about 0.1 occurrences95–95 Mya — about 0.1 occurrences95–94 Mya — about 0.1 occurrences94–94 Mya — about 0.1 occurrences94–94 Mya — about 4 occurrences94–93 Mya — about 5 occurrences93–93 Mya — about 5 occurrences93–92 Mya — about 5 occurrences92–92 Mya — about 5 occurrences92–92 Mya — about 5 occurrences92–91 Mya — about 5 occurrences91–91 Mya — about 5 occurrences91–90 Mya — about 5 occurrences90–90 Mya — about 5 occurrences90–90 Mya — about 3 occurrences101 Mya89.3 Mya

49 occurrences of Tragodesmoceras on record, most of them in the Late Cretaceous. 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

49 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

10 formations

Carlile Shale — 45.19°N, 96.75°WCarlile Shale — 44.94°N, 104.27°WCarlile Shale — 43.95°N, 104.46°WCarlile Shale — 43.90°N, 104.32°WCarlile Shale — 43.82°N, 104.21°WCarlile Shale — 43.62°N, 104.12°WCarlile Shale — 43.29°N, 103.93°WCarlile Shale — 43.31°N, 103.40°WCarlile Shale — 43.39°N, 103.39°WCarlile Shale — 43.66°N, 103.21°WSidney Island — 48.63°N, 123.29°WRedding — 40.64°N, 122.36°WRedding — 40.65°N, 122.25°WRedding — 40.67°N, 122.14°WMancos Shale — 36.18°N, 109.88°WMancos Shale — 34.74°N, 108.84°WLadd — 33.74°N, 117.62°WGreenhorn — 39.05°N, 98.20°WLa Luna — 9.65°N, 70.85°WStrehlen — 51.03°N, 13.77°EPanoche — 37.21°N, 121.22°WGreenhorn Limestone — 39.11°N, 98.35°W

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The named rock units Tragodesmoceras has been recovered from, largest first. Drawn where the rock is now, not where it formed. 6 occurrences have no formation on record, which is common for older literature.

Tragodesmoceras and its relatives

Late Cretaceous

Where Tragodesmoceras and its relatives were recorded in the Late Cretaceous.

Found in the same rock

139 taxa

The Paleobiology Database records 45 sites for Tragodesmoceras, 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

15 references

Each of the 49 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. 3 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 Tragodesmoceras

Source
iDigBio
Credit
via iDigBio
Licence
CC BY
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution
Commercial use
cannot be read from the licence given — check the record

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 itMuniericeratidae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Spath 1922