Ptychagnostus atavus

Ptychagnostus atavus is a species of agnostid trilobite. It was originally described by Swedish paleontologist Sven Axel Tullberg as Agnostus atavus in 1880. It is used in biostratigraphy as an index fossil. Its first appearance at the GSSP section in the Wheeler Shale of Utah is defined as the beginning of the Drumian Age of the Miaolingian.

Ptychagnostus atavus

TheoricienQuantique · Public Domain · 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
PtychagnostusPBDB
Diet
suspension feederPBDB, for Ptychagnostus
Life habit
nektonicPBDB, for Ptychagnostus
Motility
actively mobilePBDB, for Ptychagnostus
Vision
blindPBDB, for Ptychagnostidae

Time the record covers

At least 7.5 million years on record.

The record covers at least 504.5 Mya to 497 Mya. No occurrence read is dated outside 506.5 Mya to 486.85 Mya.

Cambrian — about 59 of 59 occurrencesCambrianOrdovician — about 0 of 59 occurrences507–506 Mya — about 2 occurrences506–506 Mya — about 7 occurrences506–505 Mya — about 8 occurrences505–504 Mya — about 8 occurrences504–504 Mya — about 6 occurrences504–503 Mya — about 5 occurrences503–502 Mya — about 3 occurrences502–501 Mya — about 3 occurrences501–501 Mya — about 3 occurrences501–500 Mya — about 3 occurrences500–499 Mya — about 3 occurrences499–499 Mya — about 2 occurrences499–498 Mya — about 2 occurrences498–497 Mya — about 2 occurrences497–497 Mya — about 1 occurrence497–496 Mya — about 0.2 occurrences496–495 Mya — about 0.1 occurrences495–495 Mya — about 0.1 occurrences495–494 Mya — about 0.1 occurrences494–493 Mya — about 0.1 occurrences493–493 Mya — about 0.1 occurrences493–492 Mya — about 0.1 occurrences492–491 Mya — about 0.1 occurrences491–490 Mya — about 0.1 occurrences490–490 Mya — about 0.1 occurrences490–489 Mya — about 0.1 occurrences489–488 Mya — about 0.1 occurrences488–488 Mya — about 0.1 occurrences488–487 Mya — about 0.1 occurrences487–486 Mya — about 0.0 occurrences504.5 Mya497 Mya507 Mya486.4 Mya

59 occurrences of Ptychagnostus atavus on record, most of them in the Cambrian. 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

59 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

17 formations

Huaqiao — 28.39°N, 109.53°EHuaqiao — 28.72°N, 109.97°EHuaqiao — 29.10°N, 110.92°EAktas — 43.53°N, 69.95°EWheeler — 39.52°N, 113.00°WWheeler — 39.22°N, 113.40°WInca — 19.50°S, 138.93°EInca — 20.25°S, 138.82°EInca — 20.21°S, 138.86°EInca — 19.98°S, 138.92°EShallow Bay — 49.02°N, 55.52°WShallow Bay — 49.83°N, 57.87°WBaguamiao — 32.22°N, 108.42°EWheeler Shale — 39.54°N, 112.92°WWheeler Shale — 39.29°N, 113.31°WYangliugang — 28.82°N, 118.60°ESecret Canyon — 39.40°N, 115.95°WMarjum — 39.22°N, 113.40°WMarjum — 39.27°N, 113.31°WEl Mogallón — 28.91°N, 109.28°WAlum Shale — 58.76°N, 15.52°EMeagher — 45.76°N, 111.73°WForest Hills — 45.27°N, 66.07°WAlum Shale — 59.73°N, 10.50°EGeddes Limestone — 39.50°N, 115.98°WLincoln Peak — 39.12°N, 114.25°W

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The named rock units Ptychagnostus atavus has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Ptychagnostus atavus and its relatives

Cambrian

Where Ptychagnostus atavus and its relatives were recorded in the Cambrian.

Found in the same rock

243 taxa

The Paleobiology Database records 19 sites for Ptychagnostus atavus, 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 59 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 Ptychagnostus atavus

Credit
TheoricienQuantique
Licence
Public Domain
Commercial use
the licence allows it

No 3D scan was found. Smithsonian Open Access, MorphoSource and Sketchfab were all searched.

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 itPtychagnostus through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Tullberg 1880)