Dwardius

Dwardius is an extinct genus of cardabiodontid sharks which existed during the Cretaceous period in what is now Australia, England, France, and India. It was described by Mikael Siverson in 1999, as a new genus for the species Cretalamna woodwardi, which had been described by J. Hermann in 1977. Another species, D. siversoni, was described from the middle Albian of northeastern France by V.I. Zhelezko in 2000; the species epithet honours the author of the genus. A new species, D. sudindicus, was described by Charlie J. Underwood, Anjali Goswami, G.V.R. Prasad, Omkar Verma, and John J. Flynn in 2011, from the Cretaceous Karai Formation of India.

Dwardius

Natural History Museum UK · 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
CardabiodontidaePBDB
Diet
carnivorePBDB, for Lamniformes
Life habit
nektonicPBDB, for Lamniformes
Motility
actively mobilePBDB, for Lamniformes

Time the record covers

At least 33 million years on record.

The record covers at least 119.57 Mya to 85.7 Mya. No occurrence read is dated outside 121.4 Mya to 83.6 Mya.

Early Cretaceous — about 6 of 20 occurrencesEarly CretaceousLate Cretaceous — about 14 of 20 occurrencesLate Cretaceous122–121 Mya — about 0.3 occurrences121–120 Mya — about 0.7 occurrences110–109 Mya — about 1 occurrence109–108 Mya — about 1 occurrence108–106 Mya — about 1 occurrence106–105 Mya — about 0.4 occurrences105–104 Mya — about 0.3 occurrences104–103 Mya — about 0.3 occurrences103–101 Mya — about 0.3 occurrences101–100 Mya — about 1 occurrence100–99 Mya — about 2 occurrences99–97 Mya — about 2 occurrences97–96 Mya — about 2 occurrences96–95 Mya — about 2 occurrences95–93 Mya — about 1 occurrence93–92 Mya — about 0.6 occurrences92–91 Mya — about 0.6 occurrences91–89 Mya — about 0.4 occurrences87–85 Mya — about 0.2 occurrences85–84 Mya — about 1 occurrence84–83 Mya — about 0.5 occurrences119.57 Mya85.7 Mya122.2 Mya82.8 Mya

20 occurrences of Dwardius 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

20 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

4 formations

Hinoshima — 32.40°N, 130.40°EKarai — 11.10°N, 78.90°EHabur — 26.90°N, 70.60°EMancos Shale — 36.14°N, 109.82°W

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The named rock units Dwardius has been recovered from, largest first. Drawn where the rock is now, not where it formed. 15 occurrences have no formation on record, which is common for older literature.

Dwardius and its relatives

Late Cretaceous

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

Found in the same rock

150 taxa

The Paleobiology Database records 20 sites for Dwardius, 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

11 references

Each of the 20 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 Dwardius

Credit
Natural History Museum UK
Licence
CC0
Commercial use
the licence allows it

No 3D scan of Dwardius was found in MorphoSource and Sketchfab.

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 itCardabiodontidae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Siverson 1999