Sigmoilina

Sigmoilina is a miliolid genus, referring to the foraminiferal order Miliolida, characterized by an asymmetrical biconvex test formed by strongly overlapping chambers, one-half coil in length, that form a sigmoid (S-shaped) curve in cross section. The strongly overlapping chambers obliterate earlier ones from view resulting in the compressed biloculine appearance, differing from the squat, depressed biloculine form of Pyrgo and Biloculina. The test, as for all Miliolida, is porcelaneous and imperforate, the terminal aperture, with tooth, the only point of egress and ingress for the animal.

Sigmoilina

via iDigBio · CC BY-NC-SA · via iDigBio. 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
MiliolidaePBDB
Diet
omnivorePBDB, for Foraminifera
Life habit
semi-infaunalPBDB, for Foraminifera
Motility
stationaryPBDB, for Foraminifera

Time the record covers

At least 211 million years on record.

The record covers at least 211.18 Mya to 11.7 ka. No occurrence read is dated outside 227.3 Mya to 0 Mya.

Late Triassic — about 25 of 68 occurrencesLate TriassicEarly Jurassic — about 0 of 68 occurrencesMiddle Jurassic — about 1 of 68 occurrencesLate Jurassic — about 0 of 68 occurrencesEarly Cretaceous — about 0 of 68 occurrencesLate Cretaceous — about 0 of 68 occurrencesPaleocene — about 3 of 68 occurrencesEocene — about 4 of 68 occurrencesEoceneOligocene — about 0 of 68 occurrencesMiocene — about 21 of 68 occurrencesPliocene — about 3 of 68 occurrencesPleistocene — about 9 of 68 occurrences232–224 Mya — about 2 occurrences224–216 Mya — about 5 occurrences216–209 Mya — about 8 occurrences209–201 Mya — about 10 occurrences170–162 Mya — about 0.8 occurrences162–155 Mya — about 0.2 occurrences62–54 Mya — about 4 occurrences54–46 Mya — about 3 occurrences46–39 Mya — about 0.8 occurrences23–15 Mya — about 5 occurrences15–7.7 Mya — about 14 occurrences7.7–0 Mya — about 16 occurrences211.18 Mya11.7 ka232 Mya0 Mya

68 occurrences of Sigmoilina on record, most of them in the Late Triassic. 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

68 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

Gatun — 9.26°N, 79.91°WDachstein — 47.58°N, 14.47°EDachstein — 47.50°N, 13.50°EDachstein — 48.00°N, 16.42°EKambuhel Limestone — 47.54°N, 13.50°ENayband — 32.93°N, 52.03°ENayband — 32.95°N, 52.08°EMartinez — 38.00°N, 122.13°WMisfah — 23.17°N, 57.06°EJebel Wasa — 24.70°N, 55.87°ENimaloksa — 32.10°N, 78.17°EAsinepe Limestone — 3.00°S, 129.00°EBathurst — 33.48°S, 26.93°EIlaro — 6.70°N, 3.23°EBorbon — 1.00°N, 79.75°WCayo Agua — 9.18°N, 82.05°WEscudo de Veraguas — 9.10°N, 81.57°WZlambach — 47.62°N, 13.73°E

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The named rock units Sigmoilina has been recovered from, largest first. Drawn where the rock is now, not where it formed. 44 occurrences have no formation on record, which is common for older literature.

Sigmoilina and its relatives

Late Triassic

Where Sigmoilina and its relatives were recorded in the Late Triassic.

Found in the same rock

1,086 taxa

The Paleobiology Database records 63 sites for Sigmoilina, 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

35 references

Each of the 68 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. 23 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 Sigmoilina

Source
iDigBio
Credit
via iDigBio
Licence
CC BY-NC-SA
Commercial use
the licence does not allow it

CT scan

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
Sigmoilina sp. · l-cb

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 itMiliolidae through timeFormations of the Late TriassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Schlumberger 1887