Megapitaria squalida

Megapitaria squalida, the chocolate clam, is a species of bivalve mollusc in the family Veneridae. It was first described to science by George Brettingham Sowerby, a British conchologist, in 1835. The type specimen was collected by Hugh Cuming. Fossil evidence suggests that this species may be as old as 3.6 million years.

Megapitaria squalida

Jordanroderick · CC BY-SA 4.0 · 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
chocolate clamPBDB
Sits inside
Macrocallista (Megapitaria)PBDB
Diet
suspension feederPBDB, for Macrocallista (Megapitaria)
Life habit
infaunalPBDB, for Macrocallista (Megapitaria)
Motility
facultatively mobilePBDB, for Macrocallista (Megapitaria)
Vision
blindPBDB, for Bivalvia

Time the record covers

At least 2.4 million years on record.

The record covers at least 2.58 Mya to 129 ka. No occurrence read is dated outside 5.333 Mya to 11.7 ka.

Miocene — about 0 of 21 occurrencesPliocene — about 5 of 21 occurrencesPliocenePleistocene — about 16 of 21 occurrencesPleistoceneHolocene — about 0 of 21 occurrences5.4–5.3 Mya — about 0.0 occurrences5.3–5.1 Mya — about 0.1 occurrences5.1–4.9 Mya — about 0.1 occurrences4.9–4.7 Mya — about 0.1 occurrences4.7–4.5 Mya — about 0.1 occurrences4.5–4.3 Mya — about 0.1 occurrences4.3–4.1 Mya — about 0.1 occurrences4.1–3.9 Mya — about 0.1 occurrences3.9–3.7 Mya — about 0.1 occurrences3.7–3.5 Mya — about 0.4 occurrences3.5–3.3 Mya — about 0.8 occurrences3.3–3.1 Mya — about 0.8 occurrences3.1–2.9 Mya — about 0.8 occurrences2.9–2.7 Mya — about 0.8 occurrences2.7–2.5 Mya — about 0.6 occurrences2.5–2.3 Mya — about 0.3 occurrences2.3–2.1 Mya — about 0.3 occurrences2.1–1.9 Mya — about 0.3 occurrences1.9–1.8 Mya — about 0.3 occurrences1.8–1.6 Mya — about 0.2 occurrences1.6–1.4 Mya — about 0.2 occurrences1.4–1.2 Mya — about 0.2 occurrences1.2–972 ka Mya — about 0.2 occurrences972 ka–778 ka Mya — about 0.2 occurrences778 ka–583 ka Mya — about 0.1 occurrences583 ka–389 ka Mya — about 0.1 occurrences389 ka–194 ka Mya — about 0.1 occurrences194 ka–0 Mya — about 14 occurrences2.58 Mya129 ka5.8 Mya0 Mya

21 occurrences of Megapitaria squalida 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

21 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

5 formations

Palos Verdes Sand — 33.80°N, 118.16°WPalos Verdes Sand — 33.60°N, 117.88°WPico — 34.42°N, 118.70°WPico — 34.36°N, 118.56°WMulege — 27.05°N, 111.97°WArmuelles — 8.03°N, 82.92°WCanoa — 0.20°N, 80.27°W

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The named rock units Megapitaria squalida has been recovered from, largest first. Drawn where the rock is now, not where it formed. 11 occurrences have no formation on record, which is common for older literature.

Megapitaria squalida and its relatives

Pleistocene

Where Megapitaria squalida and its relatives were recorded in the Pleistocene.

Found in the same rock

814 taxa

The Paleobiology Database records 17 sites for Megapitaria squalida, 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

14 references

Each of the 21 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. 2 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 Megapitaria squalida

Credit
Jordanroderick
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan of Megapitaria squalida was found in MorphoSource and Sketchfab.

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 itMacrocallista (Megapitaria) through timeFormations of the PleistoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Sowerby 1833)