Micragnostus

Micragnostus is a genus of trilobites in the order Agnostida, which existed in what is now north Wales. It was described by Howell in 1935, and the type species is Micragnostus calvus, which was originally described as a species of Agnostus by Lake in 1906.

Micragnostus

via GBIF · CC0 · via GBIF. 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
AgnostidaePBDB
Diet
detritivorePBDB, for Agnostida
Life habit
epifaunalPBDB, for Agnostida
Motility
slow-movingPBDB, for Agnostida
Vision
blindPBDB, for Agnostidae

Time the record covers

At least 18 million years on record.

The record covers at least 494.2 Mya to 475.3 Mya. No occurrence read is dated outside 497 Mya to 468 Mya.

Cambrian — about 169 of 226 occurrencesCambrianOrdovician — about 57 of 226 occurrencesOrdovician498–497 Mya — about 2 occurrences497–496 Mya — about 5 occurrences496–495 Mya — about 7 occurrences495–494 Mya — about 9 occurrences494–493 Mya — about 17 occurrences493–492 Mya — about 39 occurrences492–491 Mya — about 17 occurrences491–490 Mya — about 20 occurrences490–489 Mya — about 20 occurrences489–488 Mya — about 19 occurrences488–487 Mya — about 13 occurrences487–486 Mya — about 5 occurrences486–485 Mya — about 5 occurrences485–484 Mya — about 5 occurrences484–483 Mya — about 5 occurrences483–481 Mya — about 5 occurrences481–480 Mya — about 5 occurrences480–479 Mya — about 5 occurrences479–478 Mya — about 5 occurrences478–477 Mya — about 5 occurrences477–476 Mya — about 2 occurrences476–475 Mya — about 0.6 occurrences475–474 Mya — about 2 occurrences474–473 Mya — about 2 occurrences473–472 Mya — about 2 occurrences472–471 Mya — about 2 occurrences471–470 Mya — about 0.6 occurrences470–469 Mya — about 0.4 occurrences469–468 Mya — about 0.4 occurrences468–467 Mya — about 0.2 occurrences494.2 Mya475.3 Mya497.6 Mya467.4 Mya

226 occurrences of Micragnostus 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

226 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

45 formations

Bestogai — 43.53°N, 69.95°ETinu — 17.37°N, 97.17°WTinu — 17.47°N, 97.23°WTinu — 17.03°N, 97.23°WTinu — 17.03°N, 96.57°WLampazar — 23.00°S, 66.00°WLampazar — 23.15°S, 65.60°WLampazar — 23.05°S, 65.47°WLampazar — 23.17°S, 65.44°WLampazar — 23.88°S, 65.71°WLampazar — 23.62°S, 65.69°WLampazar — 22.92°S, 66.62°WMachari — 37.31°N, 128.44°ESiyangshan — 28.85°N, 118.65°ESiyangshan — 28.90°N, 118.50°ESiyangshan — 28.82°N, 118.60°EVolcancito — 28.87°S, 67.75°WRabbitkettle — 64.59°N, 130.00°WRabbitkettle — 61.78°N, 127.95°WValhallfonna — 79.00°N, 18.00°EValhallfonna — 79.80°N, 17.76°ESurvey Peak — 52.88°N, 118.08°WShenjiawan — 29.13°N, 110.95°ETangcun — 30.67°N, 118.18°EBison Creek — 51.50°N, 116.20°WBison Creek — 51.88°N, 116.67°WBison Creek — 51.20°N, 115.65°WBison Creek — 52.27°N, 117.28°WShallow Bay — 49.83°N, 57.87°WShallow Bay — 49.92°N, 57.90°WFengshan — 41.33°N, 123.90°EFengshan — 39.77°N, 118.40°EFengshan — 42.03°N, 126.68°EFengshan — 39.75°N, 118.32°EGola Beds — 22.49°S, 140.46°EHwajeol — 37.08°N, 129.02°EHwajeol — 37.07°N, 129.15°EOgon'or — 71.28°N, 127.63°EBreadstone Shales — 51.71°N, 2.42°WSinging Creek — 43.00°S, 147.00°EGuanacuna — 17.62°S, 62.22°WGuanacuna — 22.00°S, 65.00°WSanta Rosita — 23.00°S, 66.00°WSanta Rosita — 22.77°S, 66.20°WDeadwood — 44.63°N, 104.38°WTomahawk — 22.70°S, 133.05°ETomahawk — 22.50°S, 136.93°ESeydisehir — 37.42°N, 43.63°E

Loading coastlines…

The named rock units Micragnostus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 21 further formations hold fewer occurrences each and are not listed. 5 occurrences have no formation on record, which is common for older literature.

Micragnostus and its relatives

Cambrian

Where Micragnostus and its relatives were recorded in the Cambrian.

Found in the same rock

424 taxa

The Paleobiology Database records 116 sites for Micragnostus, 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

51 references

Each of the 226 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. 39 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 Micragnostus

Source
GBIF
Credit
via GBIF
Licence
CC0
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 itAgnostidae through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Howell 1935)