Amphistegina

Searched as Amphistegina sp.. The Paleobiology Database treats Amphistegina as the accepted name.

Amphistegina is a genus of foraminiferal protists included in the Rotaliida with a stratigraphic range extending from the Eocene to recent and a cosmopolitan distribution. The test is an asymmetrically biconvex trochospiral that may be bi-involute or partially evolute on the spiral side. Chambers are numerous, broad. and low, strongly curved back at the periphery to form chamber prolongations. The umbilical side is stellate, like that of Asterigerina, and has a distinct umbilical plug. The wall is calcareous, optically radial; the surface finely perforate and smooth overall. The periphery angular to carinate (keeled); the aperture an interiomarginal slit on the umbilical side, bordered by a lip.

Amphistegina

Carlos Natário · 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
Sits inside
AmphisteginidaePBDB
Diet
carnivorePBDB
Life habit
semi-infaunalPBDB, for Foraminifera
Motility
stationaryPBDB, for Rotaliina
Environment
outer shelf,marinePBDB, for Rotaliina

Time the record covers

At least 48 million years on record.

The record covers at least 48.07 Mya to 11.7 ka. No occurrence read is dated outside 66 Mya to 0 Mya.

Late Cretaceous — about 0 of 691 occurrencesPaleocene — about 0 of 691 occurrencesPaleoceneEocene — about 23 of 691 occurrencesEoceneOligocene — about 119 of 691 occurrencesOligoceneMiocene — about 237 of 691 occurrencesMiocenePliocene — about 42 of 691 occurrencesPleistocene — about 259 of 691 occurrences67–65 Mya — about 0.0 occurrences65–63 Mya — about 0.1 occurrences63–61 Mya — about 0.1 occurrences61–58 Mya — about 0.1 occurrences58–56 Mya — about 0.1 occurrences56–54 Mya — about 1 occurrence54–52 Mya — about 1 occurrence52–49 Mya — about 1 occurrence49–47 Mya — about 2 occurrences47–45 Mya — about 3 occurrences45–43 Mya — about 3 occurrences43–40 Mya — about 3 occurrences40–38 Mya — about 2 occurrences38–36 Mya — about 3 occurrences36–34 Mya — about 4 occurrences34–31 Mya — about 16 occurrences31–29 Mya — about 16 occurrences29–27 Mya — about 20 occurrences27–25 Mya — about 37 occurrences25–22 Mya — about 35 occurrences22–20 Mya — about 28 occurrences20–18 Mya — about 20 occurrences18–16 Mya — about 22 occurrences16–13 Mya — about 37 occurrences13–11 Mya — about 39 occurrences11–9.0 Mya — about 26 occurrences9.0–6.7 Mya — about 34 occurrences6.7–4.5 Mya — about 32 occurrences4.5–2.2 Mya — about 48 occurrences2.2–0 Mya — about 254 occurrences48.07 Mya11.7 ka67 Mya0 Mya

691 occurrences of Amphistegina 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

691 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

53 formations

Qom Formation — 33.51°N, 51.99°EQom Formation — 34.51°N, 50.95°ETortonian Limestone — 34.99°N, 24.75°ELithothamnion limestone — 45.19°N, 16.37°ELower Coralline Limestone — 35.92°N, 14.42°EGuitar Formation — 9.12°N, 92.80°ENummulitic Limestone — 43.78°N, 7.56°ENummulitic Limestone — 44.00°N, 7.74°ENummulitic Limestone — 43.96°N, 6.69°ENummulitic Limestone — 43.38°N, 6.87°EMolare — 44.37°N, 8.20°EMolare — 44.50°N, 8.48°ESedini — 40.82°N, 8.83°EMonte S Angelo — 42.69°N, 9.32°EEl Bosque — 37.90°N, 1.57°WMut — 36.83°N, 33.47°EAntigua — 17.15°N, 61.78°WAntigua — 17.17°N, 61.85°WAntigua — 17.03°N, 61.68°WCalcare Massiccio — 42.93°N, 11.87°EBakhtiari — 32.06°N, 50.81°EPakhna — 34.97°N, 34.08°ESan Juan — 16.67°N, 93.08°WRosignano Limestone — 43.40°N, 10.47°ERosignano Limestone — 43.50°N, 10.43°EBrasso — 10.59°N, 61.13°WCala di Labra — 41.37°N, 9.18°ECalcareniti di Castelgomberto — 45.48°N, 11.58°EQom — 35.50°N, 48.42°EPesco Falcone — 42.17°N, 14.10°ERoaia — 47.59°N, 24.02°ECalcari a Briozoi e Litotamni — 41.42°N, 13.97°ECalcari a Briozoi e Litotamni — 41.49°N, 13.86°E

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The named rock units Amphistegina has been recovered from, largest first. Drawn where the rock is now, not where it formed. 29 further formations hold fewer occurrences each and are not listed. 449 occurrences have no formation on record, which is common for older literature.

Amphistegina and its relatives

Pleistocene

Where Amphistegina and its relatives were recorded in the Pleistocene.

Found in the same rock

943 taxa

The Paleobiology Database records 514 sites for Amphistegina, and this reads 240 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

113 references

Each of the 691 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. 101 further references are not listed. Each entry links to doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content2

Picture of Amphistegina

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

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
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 itAmphisteginidae through timeFormations of the PleistoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. d'Orbigny 1826