Xiphodolamia

Xiphodolamia is a rare extinct genus of mackerel shark which lived during the Eocene epoch. It is the only known member of the extinct family Xiphodolamiidae. It is only known from isolated teeth, but has been found in Europe, Africa, and Asia. It is assumed to be pelagic, occurring more frequently in deeper water deposits, most notably the London Clay and Eocene deposits in Denmark. It is distinguished by its rectangular root and twisted blade, unique among mackerel sharks. It is unclear what niche this specialized dentition helped exploit.

Xiphodolamia

Mason Hintermeister · CC BY-SA 4.0 · 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
XiphodolamiidaePBDB
Diet
carnivorePBDB, for Lamniformes
Life habit
nektonicPBDB, for Lamniformes
Motility
actively mobilePBDB, for Lamniformes

Time the record covers

At least 32 million years on record.

The record covers at least 48.07 Mya to 15.98 Mya. No occurrence read is dated outside 56 Mya to 5.333 Mya.

Paleocene — about 0 of 28 occurrencesEocene — about 25 of 28 occurrencesEoceneOligocene — about 0 of 28 occurrencesMiocene — about 3 of 28 occurrencesMiocenePliocene — about 0 of 28 occurrences57–55 Mya — about 1 occurrence55–54 Mya — about 2 occurrences54–52 Mya — about 2 occurrences52–50 Mya — about 2 occurrences50–48 Mya — about 2 occurrences48–46 Mya — about 2 occurrences46–45 Mya — about 2 occurrences45–43 Mya — about 2 occurrences43–41 Mya — about 2 occurrences41–39 Mya — about 0.2 occurrences39–38 Mya — about 0.1 occurrences38–36 Mya — about 3 occurrences36–34 Mya — about 3 occurrences34–32 Mya — about 0.5 occurrences24–22 Mya — about 0.2 occurrences22–20 Mya — about 0.3 occurrences20–18 Mya — about 0.3 occurrences18–17 Mya — about 0.3 occurrences17–15 Mya — about 0.7 occurrences15–13 Mya — about 0.6 occurrences13–11 Mya — about 0.1 occurrences11–9.6 Mya — about 0.1 occurrences9.6–7.8 Mya — about 0.1 occurrences7.8–6.1 Mya — about 0.1 occurrences6.1–4.3 Mya — about 0.0 occurrences48.07 Mya15.98 Mya57 Mya4 Mya

28 occurrences of Xiphodolamia on record, most of them in the Eocene. 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

28 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

18 formations

Tielt — 51.01°N, 3.23°EWadi Esh-Shallala — 31.57°N, 37.12°EWadi Esh-Shallala — 30.85°N, 35.85°ESamlat — 23.36°N, 16.03°WSamlat — 23.56°N, 15.91°WLondon Clay — 51.40°N, 0.83°ELondon Clay — 51.85°N, 1.28°EKirkwood — 39.56°N, 75.33°WManasquan — 39.93°N, 74.75°WDaba'a — 29.16°N, 27.43°EFürstenau — 52.59°N, 7.22°ECadell Marl — 34.10°S, 139.67°EScotland — 13.21°N, 59.56°WDongen — 53.16°N, 6.22°ELillebælt Clay — 55.60°N, 9.81°ECane River — 31.88°N, 93.37°WAlgarrobo Beds — 33.36°S, 71.68°WTologaysor — 47.49°N, 55.26°EPabdeh — 33.03°N, 47.45°EKressenberg — 47.93°N, 12.97°ESuzak — 41.65°N, 64.66°E

Loading coastlines…

The named rock units Xiphodolamia has been recovered from, largest first. Drawn where the rock is now, not where it formed. 5 occurrences have no formation on record, which is common for older literature.

Xiphodolamia and its relatives

Eocene

Where Xiphodolamia and its relatives were recorded in the Eocene.

Found in the same rock

339 taxa

The Paleobiology Database records 28 sites for Xiphodolamia, 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

19 references

Each of the 28 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. 7 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 Xiphodolamia

Credit
Mason Hintermeister
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan of Xiphodolamia 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 itXiphodolamiidae through timeFormations of the EoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Leidy 1877