Pisidium

Pisidium is a genus of very small or minute freshwater clams known as pill clams or pea clams, aquatic bivalve molluscs in the family Sphaeriidae, the pea clams and fingernail clams.

Pisidium

Michal Horsák · CC BY 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
Also called
pea clamPBDB
Sits inside
PisidiinaePBDB
Diet
suspension feederPBDB, for Bivalvia
Life habit
infaunalPBDB, for Bivalvia
Motility
facultatively mobilePBDB, for Bivalvia
Vision
blindPBDB, for Bivalvia
Environment
freshwaterPBDB, for Sphaeriidae

Time the record covers

At least 65 million years on record.

The record covers at least 66 Mya to 11.7 ka. No occurrence read is dated outside 72.2 Mya to 0 Mya.

Late Cretaceous — about 1 of 84 occurrencesLate CretaceousPaleocene — about 0 of 84 occurrencesEocene — about 0 of 84 occurrencesOligocene — about 3 of 84 occurrencesOligoceneMiocene — about 23 of 84 occurrencesMiocenePliocene — about 11 of 84 occurrencesPleistocene — about 44 of 84 occurrences74–71 Mya — about 0.2 occurrences71–69 Mya — about 0.4 occurrences69–66 Mya — about 0.4 occurrences66–64 Mya — about 0.0 occurrences34–32 Mya — about 0.3 occurrences32–29 Mya — about 0.4 occurrences29–27 Mya — about 0.5 occurrences27–25 Mya — about 1 occurrence25–22 Mya — about 0.7 occurrences17–15 Mya — about 4 occurrences15–12 Mya — about 6 occurrences12–9.8 Mya — about 3 occurrences9.8–7.4 Mya — about 4 occurrences7.4–4.9 Mya — about 7 occurrences4.9–2.5 Mya — about 10 occurrences2.5–0 Mya — about 46 occurrences66 Mya11.7 ka74 Mya0 Mya

84 occurrences of Pisidium on record, most of them in the Pleistocene. The Paleobiology Database records this as a living group. 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

84 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

16 formations

Afyon — 39.00°N, 31.00°EVistula — 54.28°N, 19.48°EVistula — 53.94°N, 19.33°EBohio — 9.17°N, 79.85°WLecze — 54.23°N, 19.46°ELecze — 54.27°N, 19.48°Efacies à Congeria — 45.05°N, 7.93°EAlturas — 40.16°N, 120.27°WKarterit Cliff — 0.50°S, 36.15°ELower Bone Bed — 39.25°N, 8.68°WVenta del Moro-Villatoya — 39.48°N, 1.35°WSanta Maria di Ciciliano — 42.65°N, 12.49°EFeistring — 47.55°N, 15.25°EPebas — 4.17°S, 72.38°WLefkon — 41.17°N, 23.50°EManix — 34.80°N, 117.00°WScollard — 52.33°N, 113.12°WTruckee — 39.87°N, 118.75°W

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The named rock units Pisidium has been recovered from, largest first. Drawn where the rock is now, not where it formed. 60 occurrences have no formation on record, which is common for older literature.

Pisidium and its relatives

Pleistocene

Where Pisidium and its relatives were recorded in the Pleistocene.

Found in the same rock

1,501 taxa

The Paleobiology Database records 65 sites for Pisidium, 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

42 references

Each of the 84 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. 30 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 Pisidium

Credit
Michal Horsák
Licence
CC BY 3.0
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 itPisidiinae through timeFormations of the PleistoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Pfeiffer 1821