Sphenodiscus

Sphenodiscus is an extinct genus of acanthoceratacean ammonite. The genus has been found from many continents and is thought to have had a large global distribution during the Maastrichtian stage of the Late Cretaceous. It was one of the last ammonoids to have evolved before the entire subclass became extinct during the Paleocene, which was directly after the Cretaceous–Paleogene extinction event.

Sphenodiscus

Smokeybjb · 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
SphenodiscidaePBDB
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 33 million years on record.

Every occurrence read is dated to somewhere between 93.9 Mya and 61.66 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Late Cretaceous — about 242 of 242 occurrencesLate CretaceousPaleocene — about 0 of 242 occurrencesPaleocene95–93 Mya — about 0.0 occurrences93–92 Mya — about 0.0 occurrences92–91 Mya — about 0.0 occurrences91–90 Mya — about 0.0 occurrences90–89 Mya — about 0.0 occurrences89–88 Mya — about 0.0 occurrences88–87 Mya — about 0.0 occurrences87–86 Mya — about 0.0 occurrences86–84 Mya — about 0.0 occurrences84–83 Mya — about 0.3 occurrences83–82 Mya — about 1 occurrence82–81 Mya — about 1 occurrence81–80 Mya — about 1 occurrence80–79 Mya — about 1 occurrence79–78 Mya — about 1 occurrence78–77 Mya — about 1 occurrence77–76 Mya — about 1 occurrence76–74 Mya — about 1 occurrence74–73 Mya — about 1 occurrence73–72 Mya — about 2 occurrences72–71 Mya — about 41 occurrences71–70 Mya — about 41 occurrences70–69 Mya — about 41 occurrences69–68 Mya — about 41 occurrences68–67 Mya — about 41 occurrences67–65 Mya — about 22 occurrences65–64 Mya — about 0.1 occurrences64–63 Mya — about 0.1 occurrences63–62 Mya — about 0.1 occurrences62–61 Mya — about 0.0 occurrences94.5 Mya61 Mya

242 occurrences of Sphenodiscus 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

242 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

29 formations

Escondido — 29.34°N, 98.89°WEscondido — 29.39°N, 99.02°WEscondido — 29.35°N, 99.06°WEscondido — 29.27°N, 99.05°WEscondido — 29.25°N, 99.24°WEscondido — 29.32°N, 99.27°WEscondido — 29.25°N, 99.28°WEscondido — 29.16°N, 99.47°WEscondido — 29.18°N, 99.66°WEscondido — 29.11°N, 99.82°WEscondido — 29.10°N, 99.88°WEscondido — 29.06°N, 100.08°WEscondido — 29.03°N, 100.25°WEscondido — 28.87°N, 100.16°WEscondido — 28.97°N, 100.24°WEscondido — 28.92°N, 100.27°WEscondido — 28.72°N, 100.47°WEscondido — 28.59°N, 100.40°WEscondido — 28.53°N, 100.32°WEscondido — 28.60°N, 100.25°WEscondido — 28.61°N, 100.14°WEscondido — 28.26°N, 100.27°WCorsicana Marl — 33.10°N, 95.54°WCorsicana Marl — 33.10°N, 95.99°WCorsicana Marl — 32.92°N, 96.11°WCorsicana Marl — 32.87°N, 96.20°WCorsicana Marl — 32.85°N, 96.21°WCorsicana Marl — 32.53°N, 96.27°WCorsicana Marl — 32.22°N, 96.31°WCorsicana Marl — 32.06°N, 96.47°WCorsicana Marl — 32.06°N, 96.43°WCorsicana Marl — 31.81°N, 96.54°WCorsicana Marl — 31.74°N, 96.61°WCorsicana Marl — 31.40°N, 96.74°WCorsicana Marl — 30.37°N, 97.45°WCorsicana Marl — 30.32°N, 97.53°WCorsicana Marl — 30.23°N, 97.52°WCorsicana Marl — 29.95°N, 97.71°WCorsicana Marl — 29.72°N, 97.90°WCorsicana Marl — 29.58°N, 98.04°WCorsicana Marl — 29.49°N, 98.19°WCorsicana Marl — 29.39°N, 98.71°WCorsicana Marl — 29.48°N, 98.81°WCorsicana Marl — 29.18°N, 99.02°WCorsicana Marl — 31.30°N, 96.90°WSevern — 38.80°N, 77.00°WSevern — 38.89°N, 76.85°WSevern — 38.92°N, 76.85°WSevern — 39.04°N, 76.57°WSevern — 39.33°N, 76.03°WSevern — 38.83°N, 76.85°WPrairie Bluff — 34.51°N, 88.92°WPrairie Bluff — 34.25°N, 88.97°WPrairie Bluff — 33.46°N, 88.79°WPrairie Bluff — 33.38°N, 88.74°WPrairie Bluff — 33.07°N, 88.61°WPrairie Bluff — 33.05°N, 88.56°WPrairie Bluff — 32.23°N, 87.50°WPrairie Bluff — 32.07°N, 87.33°WPrairie Bluff — 32.04°N, 86.79°WPrairie Bluff — 31.98°N, 86.00°WPrairie Bluff — 31.98°N, 85.92°WPrairie Bluff — 34.49°N, 89.01°WProvidence — 31.92°N, 85.82°WProvidence — 31.89°N, 85.70°WProvidence — 31.84°N, 85.22°WProvidence — 31.76°N, 85.13°WProvidence — 31.73°N, 85.12°WProvidence — 31.80°N, 85.00°WEscondido — 27.02°N, 100.52°WEscondido — 25.05°N, 100.12°WEscondido — 28.48°N, 101.02°WEscondido — 27.60°N, 99.97°WEscondido — 28.08°N, 100.33°WEscondido — 28.23°N, 100.22°WEscondido — 27.53°N, 103.17°WEscondido — 27.75°N, 101.23°WFox Hills — 45.14°N, 100.88°WFox Hills — 40.62°N, 104.82°WFox Hills — 40.44°N, 104.86°WFox Hills — 43.36°N, 104.26°WFox Hills — 43.25°N, 104.29°WFox Hills — 43.18°N, 104.35°WFox Hills — 44.26°N, 102.38°WChiwapa — 34.63°N, 88.85°WChiwapa — 34.60°N, 88.95°WChiwapa — 34.46°N, 88.90°WChiwapa — 34.36°N, 88.92°WOwl Creek — 34.82°N, 88.88°WOwl Creek — 34.75°N, 88.91°WOwl Creek — 37.01°N, 89.85°WPeedee — 34.04°N, 79.80°WPeedee — 33.99°N, 79.52°WPeedee — 33.91°N, 79.45°WPeedee — 33.76°N, 79.30°WPeedee — 34.27°N, 77.95°WPeedee — 34.05°N, 80.02°WNkporo Shale — 5.20°N, 8.18°ENkporo Shale — 5.82°N, 7.92°EKemp Clay — 30.27°N, 97.74°WKemp Clay — 29.42°N, 98.49°WKemp Clay — 33.14°N, 95.60°WPierre Shale — 43.27°N, 104.27°WPierre Shale — 40.17°N, 104.99°WRipley — 31.79°N, 85.13°WRipley — 34.49°N, 89.01°WTinton — 40.30°N, 74.10°WTinton — 40.39°N, 74.19°WNacatoch Sand — 32.59°N, 96.31°WCerro del Pueblo — 25.50°N, 101.40°WGramame — 7.25°S, 34.80°WFox Hills Sandstone — 40.53°N, 107.75°WFox Hills Sandstone — 40.15°N, 105.02°WDakhla — 26.52°N, 27.66°EArkadelphia marl — 33.76°N, 93.65°WHornerstown — 39.76°N, 75.13°WValudavur — 12.03°N, 79.75°EMaastricht — 50.88°N, 5.75°E

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The named rock units Sphenodiscus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 5 further formations hold fewer occurrences each and are not listed. 14 occurrences have no formation on record, which is common for older literature.

Sphenodiscus and its relatives

Late Cretaceous

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

Found in the same rock

889 taxa

The Paleobiology Database records 212 sites for Sphenodiscus, 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

36 references

Each of the 242 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. 24 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 Sphenodiscus

Credit
Smokeybjb
Licence
CC BY-SA 3.0
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 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 itSphenodiscidae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Meek 1871)