Paradoxides

Paradoxides is a genus of large to very large trilobite found throughout the world during the Middle Cambrian period. One record-breaking specimen of Paradoxides davidis, described by John William Salter in 1863, is 37 cm (15 in). The cephalon was semicircular with free cheeks ending in long, narrow, recurved spines. Eyes were crescent shaped providing an almost 360° view, but only in the horizontal plane. Its elongate thorax was composed of 19–21 segments and adorned with longish, recurved pleural spines. Its pygidium was comparatively small. Paradoxides is a characteristic Middle-Cambrian trilobite of the 'Atlantic' (Avalonian) fauna. Avalonian rocks were deposited near a small continent called Avalonia in the Paleozoic Iapetus Ocean. Avalonian beds are now in a narrow strip along the East Coast of North America, and in Europe.

Paradoxides

Ryan Schwark · CC0 · 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
ParadoxididaePBDB
Diet
carnivorePBDB, for Paradoxidoidea
Life habit
low-level epifaunalPBDB, for Redlichiida
Motility
fast-movingPBDB, for Redlichiida
Vision
well-developedPBDB, for Paradoxididae
Environment
marinePBDB, for Trilobita

Time the record covers

At least 7.7 million years on record.

The record covers at least 508.2 Mya to 500.5 Mya. No occurrence read is dated outside 516.2 Mya to 497 Mya.

Cambrian — about 138 of 138 occurrencesCambrian517–516 Mya — about 0.0 occurrences516–515 Mya — about 0.4 occurrences515–515 Mya — about 0.4 occurrences515–514 Mya — about 0.4 occurrences514–513 Mya — about 0.4 occurrences513–513 Mya — about 0.4 occurrences513–512 Mya — about 0.4 occurrences512–511 Mya — about 0.4 occurrences511–511 Mya — about 0.4 occurrences511–510 Mya — about 0.4 occurrences510–509 Mya — about 0.5 occurrences509–509 Mya — about 0.6 occurrences509–508 Mya — about 2 occurrences508–507 Mya — about 4 occurrences507–507 Mya — about 4 occurrences507–506 Mya — about 8 occurrences506–505 Mya — about 9 occurrences505–505 Mya — about 9 occurrences505–504 Mya — about 10 occurrences504–503 Mya — about 10 occurrences503–503 Mya — about 10 occurrences503–502 Mya — about 10 occurrences502–501 Mya — about 10 occurrences501–501 Mya — about 10 occurrences501–500 Mya — about 9 occurrences500–499 Mya — about 8 occurrences499–499 Mya — about 6 occurrences499–498 Mya — about 5 occurrences498–497 Mya — about 5 occurrences497–497 Mya — about 1 occurrence508.2 Mya500.5 Mya516.7 Mya496.5 Mya

138 occurrences of Paradoxides 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

138 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

33 formations

Jince — 49.78°N, 13.97°EJince — 49.00°N, 14.00°EChamberlain's Brook — 45.28°N, 66.03°WChamberlain's Brook — 45.47°N, 65.63°WChamberlain's Brook — 47.49°N, 53.02°WChamberlain's Brook — 45.43°N, 65.63°WChamberlain's Brook — 46.27°N, 66.07°WChamberlain's Brook — 45.27°N, 66.07°WSosink — 37.30°N, 40.30°ESosink — 37.80°N, 37.75°EMurero — 41.17°N, 1.48°WMurero — 41.66°N, 1.77°WMurero — 41.52°N, 1.50°WFjällbränna — 64.43°N, 15.54°EFjällbränna — 64.25°N, 15.85°EKoruk — 37.42°N, 43.63°EUsarzow Sandstone — 50.72°N, 21.52°EFerrals — 43.40°N, 2.63°ELos Villares — 38.00°N, 4.80°WOville — 43.00°N, 5.00°WOville — 42.85°N, 5.87°WSkryje — 49.95°N, 13.77°EAsbill Pond — 34.00°N, 82.00°WLower Alum Shale — 55.00°N, 15.00°ESkryje Shale — 49.97°N, 13.77°EAlum Shale — 59.75°N, 10.50°EAlum Shale — 59.73°N, 10.50°EAlum Shale — 58.76°N, 15.52°EManuel River — 45.42°N, 65.66°WManuel River — 45.33°N, 65.53°WKuonamka — 71.23°N, 117.17°EKuonamka — 66.50°N, 116.00°EUpper Comley Sandstone — 52.00°N, 2.00°WQuartzites et Poudingues de Trémentines — 47.09°N, 0.25°WSlowiec Sandstone — 50.68°N, 21.37°ESenice — 49.88°N, 15.57°EValdemiedes — 41.17°N, 1.48°WLa Gardie — 43.40°N, 2.63°E

Loading coastlines…

The named rock units Paradoxides has been recovered from, largest first. Drawn where the rock is now, not where it formed. 9 further formations hold fewer occurrences each and are not listed. 7 occurrences have no formation on record, which is common for older literature.

Paradoxides and its relatives

Cambrian

Where Paradoxides and its relatives were recorded in the Cambrian.

Found in the same rock

329 taxa

The Paleobiology Database records 89 sites for Paradoxides, 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

43 references

Each of the 138 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. 31 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 Paradoxides

Credit
Ryan Schwark
Licence
CC0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC0 Public Domain
Commercial use
the licence allows it

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 itParadoxididae through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Brongniart 1822