Hesperornithidae

Hesperornithes is an extinct and highly specialized group of aquatic avialans closely related to the ancestors of modern birds. They inhabited both marine and freshwater habitats in the Northern Hemisphere, and include genera such as Hesperornis, Baptornis, Parahesperornis, Enaliornis, and Potamornis, all strong-swimming, predatory divers. Many of the species most specialized for swimming were completely flightless. The largest known hesperornithean, Canadaga arctica, may have reached a maximum adult length of 2.2 metres (7.2 ft).

Hesperornithidae

Loozrboy from Toronto, Canada · CC BY-SA 2.0 · 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
HesperornithiformesPBDB
Diet
carnivorePBDB, for Coelurosauria
Life habit
ground dwelling, solitaryPBDB, for Theropoda
Motility
actively mobilePBDB, for Theropoda
Environment
marinePBDB, for Hesperornithiformes

Time the record covers

At least 11 million years on record.

The record covers at least 83.6 Mya to 72.2 Mya. No occurrence read is dated outside 100.5 Mya to 66 Mya.

Early Cretaceous — about 0 of 76 occurrencesLate Cretaceous — about 76 of 76 occurrencesLate CretaceousPaleocene — about 0 of 76 occurrences101–100 Mya — about 0.0 occurrences100–99 Mya — about 0.1 occurrences99–98 Mya — about 0.1 occurrences98–96 Mya — about 0.1 occurrences96–95 Mya — about 0.1 occurrences95–94 Mya — about 0.1 occurrences94–93 Mya — about 0.1 occurrences93–92 Mya — about 0.1 occurrences92–90 Mya — about 0.1 occurrences90–89 Mya — about 0.4 occurrences89–88 Mya — about 0.8 occurrences88–87 Mya — about 0.8 occurrences87–86 Mya — about 0.8 occurrences86–84 Mya — about 2 occurrences84–83 Mya — about 3 occurrences83–82 Mya — about 7 occurrences82–81 Mya — about 7 occurrences81–80 Mya — about 7 occurrences80–78 Mya — about 7 occurrences78–77 Mya — about 7 occurrences77–76 Mya — about 7 occurrences76–75 Mya — about 7 occurrences75–74 Mya — about 7 occurrences74–72 Mya — about 7 occurrences72–71 Mya — about 2 occurrences71–70 Mya — about 1.0 occurrences70–69 Mya — about 1.0 occurrences69–68 Mya — about 1.0 occurrences68–67 Mya — about 1.0 occurrences67–65 Mya — about 0.4 occurrences83.6 Mya72.2 Mya101.2 Mya65.3 Mya

76 occurrences of Hesperornithidae 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

76 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

16 formations

Pierre Shale — 49.18°N, 98.10°WPierre Shale — 49.22°N, 98.20°WPierre Shale — 49.33°N, 98.31°WNiobrara — 39.00°N, 101.00°WNiobrara — 39.35°N, 99.88°WNiobrara — 38.92°N, 101.18°WNiobrara — 38.75°N, 100.21°WKanguk — 79.75°N, 85.60°WKanguk — 73.50°N, 79.00°WKanguk — 76.28°N, 91.20°WPierre Shale — 44.00°N, 103.25°WPierre Shale — 43.01°N, 103.30°WPierre Shale — 43.58°N, 103.20°WRybushka — 44.68°N, 39.08°ERybushka — 51.25°N, 45.36°ESmoking Hills — 69.72°N, 129.00°WMason River — 69.72°N, 129.00°WForemost — 53.25°N, 105.08°WCarlile — 49.48°N, 98.44°WJudith River — 48.97°N, 110.55°WZhuravlevskaya — 52.46°N, 64.63°EClaggett — 47.73°N, 109.62°WHell Creek — 47.80°N, 106.10°WIgnek — 69.42°N, 148.27°WOzan — 33.85°N, 93.72°WMarlbrook Marl — 34.01°N, 93.33°W

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The named rock units Hesperornithidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 14 occurrences have no formation on record, which is common for older literature.

Hesperornithidae and its relatives

Late Cretaceous

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

Found in the same rock

163 taxa

The Paleobiology Database records 58 sites for Hesperornithidae, 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

29 references

Each of the 76 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. 17 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 content1

Picture of Hesperornithidae

Credit
Loozrboy from Toronto, Canada
Licence
CC BY-SA 2.0
Commercial use
the licence allows it

No 3D scan of Hesperornithidae 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 itHesperornithiformes through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Marsh 1872)