Ptychopariida
Ptychopariida is a large, heterogeneous order of trilobite containing some of the most primitive species known. The earliest species occurred in the second half of the Lower Cambrian, and the last species did not survive the Ordovician–Silurian extinction event.

DanielCD · CC BY-SA 3.0 · 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
- LibristomaPBDB
- Diet
- carnivorePBDB, for Trilobita
- Life habit
- low-level epifaunalPBDB, for Trilobita
- Motility
- fast-movingPBDB, for Trilobita
- Environment
- marinePBDB, for Trilobita
Time the record covers
At least 89 million years on record.
The record covers at least 516 Mya to 426.7 Mya. No occurrence read is dated outside 538.8 Mya to 422.7 Mya.
6,340 occurrences of Ptychopariida 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
6,340 occurrences- Cambrian94%
- Ordovician6%
- Silurianunder 1%
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
434 formations
- Pioche Shale Formation371
- Deadwood Formation366
- Huaqiao Formation331
- Kaili Formation234
- Riley Formation231
- Gatesburg Formation140
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The named rock units Ptychopariida has been recovered from, largest first. Drawn where the rock is now, not where it formed. 410 further formations hold fewer occurrences each and are not listed. 184 occurrences have no formation on record, which is common for older literature.
Ptychopariida and its relatives
CambrianWhere Ptychopariida and its relatives were recorded in the Cambrian.
Found in the same rock
1,147 taxa- Lingulella35 sites
- Dicellomus34 sites
- Shumardia33 sites
- Hyolithes30 sites
- Coosia alethes28 sites
- Tricrepicephalus coria24 sites
- Pseudagnostina douvillei23 sites
- Blountia22 sites
- Kingstonia walcotti22 sites
- Kormagnostus seclusus22 sites
- Coosina ariston20 sites
- Cedarina dakotaensis19 sites
- Kingstonia18 sites
- Modocia nevadensis18 sites
- Geragnostus17 sites
- Micromitra17 sites
- Crepicephalus buttsi16 sites
- Peronopsis16 sites
- Arapahoia15 sites
- Uncaspis14 sites
- Crepicephalus13 sites
- Crepicephalus auratus13 sites
- Dresbachia12 sites
- Elrathia12 sites
The Paleobiology Database records at least 770 sites for Ptychopariida, and this reads 240 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
523 references- Cambrian Malyy Karatau Range, Kazakhstan259
- Corynexochida, Lichida and Asaphida259
- Trilobites, Biostratigraphy, and Lithostratigraphy of the Crepicephalus and Aphelaspis zones, Lower Deadwood formation (Marjuman and Steptoean Stages, Upper Cambrian), Black Hills, South Dakota253
- The Faunas of the Riley Formation in Central Texas230
- Trilobites of the lower Middle Cambrian Poliella denticulata biozone (new) of southeastern Nevada152
- Molluscs of the Holm Dal Formation (late Middle Cambrian), central North Greenland136
- Early Middle Cambrian Albertella biozone trilobites of the Pioche Shale, southeastern Nevada133
- Detailed trilobite biostratigraphy across the proposed GSSP for stage 5 ("Middle Cambrian" boundary) at the Wuliu-Zengjiayan section, Guizhou, China124
- Early and Mid Cambrian Trilobites from the Outer-shelf Deposits of Nevada and California, USA116
- Cambrian stratigraphy and trilobites from Henan112
- Fauna and paleoecology of the Upper Cambrian Warrior Formation of central Pennsylvania97
- High-Resolution Biostratigraphy in the Upper Cambrian ore hill Member of Gatesburg Formation, South-Central Pennsylvnia91
Each of the 6,340 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. 511 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 content2
Picture of Ptychopariida
- Source
- Wikipedia/Commons
- Credit
- DanielCD
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
3D model
- Source
- Sketchfab
- Licence
- Free Standard
- Commercial use
- cannot be read from the licence given — check the record
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 itLibristoma through timeFormations of the CambrianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Swinnerton 1915