Hemicidaris

Hemicidaris is an extinct genus of echinoids that lived from the Middle Jurassic to the Early Cretaceous. Its remains have been found in Africa, Asia, and Europe.

Hemicidaris

Eduard Solà · 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
HemicidaridaePBDB
Diet
grazer, deposit feederPBDB, for Echinoidea
Life habit
epifaunalPBDB, for Echinoidea
Motility
actively mobilePBDB, for Echinoidea
Vision
limitedPBDB, for Echinoidea
Environment
marinePBDB, for Echinodermata

Time the record covers

At least 47 million years on record.

The record covers at least 168.6 Mya to 121.4 Mya. No occurrence read is dated outside 170.9 Mya to 113.2 Mya.

Middle Jurassic — about 7 of 54 occurrencesMiddle JurassicLate Jurassic — about 33 of 54 occurrencesLate JurassicEarly Cretaceous — about 14 of 54 occurrencesEarly Cretaceous172–170 Mya — about 1 occurrence170–168 Mya — about 2 occurrences168–166 Mya — about 1.0 occurrences166–164 Mya — about 1 occurrence164–162 Mya — about 1 occurrence162–160 Mya — about 1 occurrence160–158 Mya — about 6 occurrences158–156 Mya — about 2 occurrences156–154 Mya — about 4 occurrences154–152 Mya — about 7 occurrences152–150 Mya — about 6 occurrences150–148 Mya — about 4 occurrences148–146 Mya — about 2 occurrences146–144 Mya — about 1 occurrence144–142 Mya — about 0.2 occurrences138–136 Mya — about 0.5 occurrences136–134 Mya — about 0.9 occurrences134–132 Mya — about 0.8 occurrences132–130 Mya — about 0.6 occurrences130–128 Mya — about 0.6 occurrences128–126 Mya — about 0.6 occurrences126–124 Mya — about 0.1 occurrences122–120 Mya — about 2 occurrences120–118 Mya — about 2 occurrences118–116 Mya — about 2 occurrences116–114 Mya — about 2 occurrences114–112 Mya — about 1 occurrence168.6 Mya121.4 Mya172 Mya112 Mya

54 occurrences of Hemicidaris on record, most of them in the Late Jurassic. 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

54 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

15 formations

Mt. Lysa — 50.90°N, 21.67°EMt. Lysa — 51.26°N, 21.06°EZone de Pierre jaune — 47.05°N, 7.08°EHanifa — 25.83°N, 45.17°EAgoudim — 32.28°N, 4.42°WAgoudim — 32.27°N, 4.51°WSa Wer — 10.16°N, 43.06°ESa Wer — 10.56°N, 43.00°EBahamite sequence — 53.77°N, 14.08°EVuache — 46.83°N, 6.52°EShuqra — 14.27°N, 48.57°ERingstead Coral Bed — 50.63°N, 2.35°WSüntel — 51.90°N, 10.50°EMarnes à coraux de Foug — 48.68°N, 5.78°EWheatley Limestone — 51.75°N, 1.20°WAntalo Limestone — 13.68°N, 39.58°EMormon — 40.08°N, 120.84°WDursztyn — 50.40°N, 19.06°E

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The named rock units Hemicidaris has been recovered from, largest first. Drawn where the rock is now, not where it formed. 30 occurrences have no formation on record, which is common for older literature.

Hemicidaris and its relatives

Late Jurassic

Where Hemicidaris and its relatives were recorded in the Late Jurassic.

Found in the same rock

547 taxa

The Paleobiology Database records 45 sites for Hemicidaris, 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

22 references

Each of the 54 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. 10 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 Hemicidaris

Credit
Eduard Solà
Licence
CC BY-SA 3.0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial-ShareAlike
Commercial use
the licence does not allow 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 itHemicidaridae through timeFormations of the Late JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Agassiz 1838