Illaenus crassicauda

Illaenus crassicauda is a species of trilobites belonging to the family Illaenidae. These trilobites lived in the middle Ordovician and in the Silurian age. Fossils of this species have been found in the sediments of Sweden and Russia.

Illaenus crassicauda

Hectonichus · CC BY-SA 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
Sits inside
IllaenusPBDB
Diet
carnivorePBDB, for Corynexochida
Life habit
nektobenthicPBDB, for Corynexochida
Motility
actively mobilePBDB, for Corynexochida
Vision
well-developedPBDB, for Illaenus
Environment
marinePBDB, for Trilobita

Time the record covers

At most 2.9 million years on record.

Every occurrence read is dated to somewhere between 459.7 Mya and 456.8 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Ordovician — about 2 of 2 occurrencesOrdovician460–460 Mya — about 0.0 occurrences460–460 Mya — about 0.1 occurrences460–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–459 Mya — about 0.1 occurrences459–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–458 Mya — about 0.1 occurrences458–457 Mya — about 0.1 occurrences457–457 Mya — about 0.1 occurrences457–457 Mya — about 0.1 occurrences457–457 Mya — about 0.1 occurrences457–457 Mya — about 0.1 occurrences457–457 Mya — about 0.1 occurrences457–457 Mya — about 0.0 occurrences460.2 Mya456.3 Mya

2 occurrences of Illaenus crassicauda on record, most of them in the Ordovician. 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

2 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

2 formations

Viivikonna — 59.44°N, 28.79°EMednikovo — 59.44°N, 28.79°E

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The named rock units Illaenus crassicauda has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Illaenus crassicauda and its relatives

Ordovician

Where Illaenus crassicauda and its relatives were recorded in the Ordovician.

Found in the same rock

22 taxa

The Paleobiology Database records 2 sites for Illaenus crassicauda, and this reads all of them. The number is how many of those sites it was catalogued from too.

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

1 reference

Each of the 2 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. Each entry links to doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content1

Picture of Illaenus crassicauda

Credit
Hectonichus
Licence
CC BY-SA 3.0
Commercial use
the licence allows it

No 3D scan of Illaenus crassicauda 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 itIllaenus through timeFormations of the OrdovicianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Wahlenberg 1826)