Xenacanthidae

Xenacanthiformes is an order or superorder of extinct shark-like chondrichthyans known from the Carboniferous to the Late Triassic. They were native to freshwater, marginal marine, and shallow marine habitats. Some xenacanths may have grown to lengths of 5 m (16 ft). Most xenacanths died out at the end of the Permian in the End-Permian Mass Extinction, with only a few forms surviving into the Triassic.

Xenacanthidae

Gasmasque · 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
XenacanthiformesPBDB
Diet
carnivorePBDB, for Xenacanthiformes
Life habit
nektobenthicPBDB, for Xenacanthiformes
Motility
actively mobilePBDB, for Xenacanthiformes

Time the record covers

At least 87 million years on record.

The record covers at least 315.2 Mya to 227.3 Mya. No occurrence read is dated outside 323.4 Mya to 205.7 Mya.

Carboniferous — about 22 of 100 occurrencesCarboniferousPermian — about 58 of 100 occurrencesPermianEarly Triassic — about 0 of 100 occurrencesMiddle Triassic — about 5 of 100 occurrencesLate Triassic — about 15 of 100 occurrencesLate Triassic326–322 Mya — about 0.8 occurrences322–318 Mya — about 2 occurrences318–314 Mya — about 5 occurrences314–309 Mya — about 6 occurrences309–305 Mya — about 5 occurrences305–301 Mya — about 2 occurrences301–297 Mya — about 4 occurrences297–293 Mya — about 8 occurrences293–289 Mya — about 6 occurrences289–285 Mya — about 8 occurrences285–281 Mya — about 10 occurrences281–277 Mya — about 11 occurrences277–273 Mya — about 8 occurrences273–269 Mya — about 2 occurrences269–265 Mya — about 1 occurrence265–260 Mya — about 0.2 occurrences260–256 Mya — about 0.2 occurrences256–252 Mya — about 0.2 occurrences252–248 Mya — about 0.0 occurrences248–244 Mya — about 1 occurrence244–240 Mya — about 4 occurrences240–236 Mya — about 0.4 occurrences236–232 Mya — about 0.6 occurrences232–228 Mya — about 0.6 occurrences228–224 Mya — about 2 occurrences224–220 Mya — about 3 occurrences220–216 Mya — about 3 occurrences216–212 Mya — about 3 occurrences212–207 Mya — about 3 occurrences207–203 Mya — about 1 occurrence315.2 Mya227.3 Mya326 Mya203 Mya

100 occurrences of Xenacanthidae on record, most of them in the Permian. 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

100 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

34 formations

Vale — 33.68°N, 99.58°WVale — 33.76°N, 99.55°WVale — 33.74°N, 99.41°WVale — 33.67°N, 99.78°WVale — 32.13°N, 99.75°WChinle — 34.44°N, 109.46°WChinle — 34.94°N, 109.77°WChinle — 34.68°N, 109.58°WChinle — 36.33°N, 106.47°WTecovas — 33.43°N, 101.16°WTecovas — 34.96°N, 101.70°WTecovas — 35.38°N, 102.16°WWellington — 36.16°N, 97.34°WWellington — 36.35°N, 97.43°WWellington — 36.74°N, 97.42°WWellington — 36.30°N, 97.30°WLueders — 33.75°N, 99.15°WLueders — 33.75°N, 99.12°WGarber — 36.77°N, 97.77°WGarber — 36.66°N, 97.69°WGarber — 34.45°N, 98.93°WAshfield Shale — 33.91°S, 151.19°EAshfield Shale — 34.22°S, 150.65°EEl Cobre Canyon — 36.14°N, 106.62°WKildare Capes — 46.12°N, 62.96°WKildare Capes — 46.18°N, 62.92°WKildare Capes — 46.19°N, 62.95°WCutler — 37.17°N, 109.85°WCutler — 36.16°N, 106.65°WChickasha — 36.01°N, 98.36°WChickasha — 35.94°N, 98.21°WBlack Prince Limestone — 31.73°N, 109.57°WBlack Prince Limestone — 31.77°N, 109.58°WBelle Plains — 33.58°N, 98.97°WBelle Plains — 33.69°N, 99.02°WMattoon — 38.44°N, 87.86°WBead Mountain — 34.13°N, 98.62°WBluewater Creek — 35.42°N, 108.49°WHennessey — 34.19°N, 98.79°WSan Angelo — 34.10°N, 99.73°WMaleri — 19.22°N, 79.58°EProsecne — 50.56°N, 15.66°EMoran — 32.50°N, 100.06°WArcher City — 33.45°N, 98.78°WBoruszowice — 50.45°N, 18.78°EChoza — 33.82°N, 99.56°W

Loading coastlines…

The named rock units Xenacanthidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 10 further formations hold fewer occurrences each and are not listed. 22 occurrences have no formation on record, which is common for older literature.

Xenacanthidae and its relatives

Permian

Where Xenacanthidae and its relatives were recorded in the Permian.

Found in the same rock

466 taxa

The Paleobiology Database records 75 sites for Xenacanthidae, 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

48 references

Each of the 100 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. 36 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 Xenacanthidae

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

No 3D scan of Xenacanthidae was found in Sketchfab.

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 itXenacanthiformes through timeFormations of the PermianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Fritsch 1889