Mactra

Mactra is a large genus of medium-sized marine bivalve mollusks or clams, commonly known as trough shells or duck clams. Mactra is the type genus within the family Mactridae.

Mactra

Hans Hillewaert · 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
duck clamPBDB
Sits inside
MactrinaePBDB
Diet
suspension feederPBDB
Life habit
infaunalPBDB
Motility
facultatively mobilePBDB
Vision
blindPBDB, for Bivalvia

Time the record covers

At least 192 million years on record.

The record covers at least 192.9 Mya to 11.7 ka. No occurrence read is dated outside 199.5 Mya to 0 Mya.

Late Triassic — about 0 of 296 occurrencesEarly Jurassic — about 1 of 296 occurrencesEarly JurassicMiddle Jurassic — about 0 of 296 occurrencesLate Jurassic — about 0 of 296 occurrencesLate JurassicEarly Cretaceous — about 5 of 296 occurrencesEarly CretaceousLate Cretaceous — about 13 of 296 occurrencesLate CretaceousPaleocene — about 3 of 296 occurrencesEocene — about 52 of 296 occurrencesEoceneOligocene — about 8 of 296 occurrencesMiocene — about 101 of 296 occurrencesMiocenePliocene — about 37 of 296 occurrencesPleistocene — about 55 of 296 occurrences203–197 Mya — about 0.4 occurrences197–190 Mya — about 0.6 occurrences163–156 Mya — about 0.0 occurrences156–149 Mya — about 0.1 occurrences149–142 Mya — about 0.1 occurrences142–136 Mya — about 0.4 occurrences136–129 Mya — about 0.7 occurrences129–122 Mya — about 0.9 occurrences122–115 Mya — about 0.2 occurrences115–109 Mya — about 0.8 occurrences109–102 Mya — about 2 occurrences102–95 Mya — about 1 occurrence95–88 Mya — about 2 occurrences88–81 Mya — about 2 occurrences81–75 Mya — about 4 occurrences75–68 Mya — about 4 occurrences68–61 Mya — about 1 occurrence61–54 Mya — about 3 occurrences54–47 Mya — about 3 occurrences47–41 Mya — about 12 occurrences41–34 Mya — about 36 occurrences34–27 Mya — about 6 occurrences27–20 Mya — about 22 occurrences20–14 Mya — about 39 occurrences14–6.8 Mya — about 36 occurrences6.8–0 Mya — about 118 occurrences192.9 Mya11.7 ka203 Mya0 Mya

296 occurrences of Mactra on record, most of them in the Miocene. 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

296 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

82 formations

La Meseta — 64.23°S, 56.65°WLa Meseta — 64.24°S, 56.65°WLa Meseta — 64.26°S, 56.67°WRed Crag — 51.97°N, 1.35°ERed Crag — 51.85°N, 1.28°ERed Crag — 52.03°N, 1.32°ERed Crag — 52.75°N, 1.53°ENavidad — 33.95°S, 71.75°WNavidad — 33.83°S, 71.83°WNavidad — 44.65°S, 74.58°WNavidad — 33.95°S, 71.87°WNavidad — 33.93°S, 71.85°WKirkwood — 38.94°N, 74.91°WKirkwood — 39.46°N, 75.30°WKirkwood — 39.40°N, 75.04°WKirkwood — 38.99°N, 74.82°WKirkwood — 39.08°N, 74.82°WKirkwood — 39.10°N, 74.72°WKirkwood — 39.15°N, 74.69°WSubmeseta — 64.26°S, 56.66°WSubmeseta — 64.24°S, 56.66°WSubmeseta — 64.25°S, 56.64°WSubmeseta — 64.24°S, 56.65°WDry Creek Sands — 34.85°S, 138.60°EDry Creek Sands — 34.88°S, 138.49°EDry Creek Sands — 34.89°S, 138.56°EMonte Leon Fm — 50.12°S, 68.48°WMonte Leon Fm — 50.37°S, 69.05°WMonte Leon Fm — 50.23°S, 68.92°WBaghmara — 25.17°N, 90.67°EBaghmara — 25.27°N, 90.23°EBerada — 51.10°N, 5.80°EForemost — 49.10°N, 110.82°WForemost — 49.10°N, 110.95°WForemost — 49.01°N, 111.08°WForemost — 49.27°N, 112.83°WForemost — 49.77°N, 112.45°WChengapara — 25.33°N, 90.23°EChengapara — 25.17°N, 90.67°EPirabas — 0.80°S, 47.13°WPirabas — 0.48°S, 48.17°WPirabas — 1.05°S, 47.16°WPirabas — 0.60°S, 47.31°WOtahuhu — 36.95°S, 174.84°EMammaliferous Crag — 52.58°N, 1.38°WCoralline Crag — 52.12°N, 1.55°ECoralline Crag — 52.75°N, 1.53°EWaiomio — 40.03°S, 175.48°EFalun de Sainte-Avit — 43.91°N, 0.66°WCook Mountain — 31.09°N, 95.95°WCook Mountain — 31.25°N, 95.72°WKoronia — 35.08°N, 33.17°EKoronia — 35.05°N, 33.05°EChipola — 30.44°N, 85.19°WCarbonera — 6.80°N, 73.58°WCarbonera — 8.33°N, 73.67°WNaseby Greensand — 45.02°S, 170.12°EItahana — 36.00°N, 139.00°ETalara — 5.87°S, 80.62°WTalara — 5.13°S, 81.17°W

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The named rock units Mactra has been recovered from, largest first. Drawn where the rock is now, not where it formed. 58 further formations hold fewer occurrences each and are not listed. 92 occurrences have no formation on record, which is common for older literature.

Mactra and its relatives

Miocene

Where Mactra and its relatives were recorded in the Miocene.

Found in the same rock

3,863 taxa

The Paleobiology Database records 183 sites for Mactra, and this reads all of them. Of that, one read hit the database's own return limit, so every count below is a floor rather than a total. 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

122 references

Each of the 296 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. 110 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 content3

Picture of Mactra

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

Photogrammetry

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
mactra sp. · MST:PALEO:MST-SP-9001

3D model

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

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 itMactrinae through timeFormations of the MioceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Linnaeus 1767