Isoetites horridus

via iDigBio · CC0 · 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
- IsoetitesPBDB
- Diet
- "photoautotroph"PBDB, for Streptophyta
- Environment
- freshwater,terrestrialPBDB, for Lycopodiophyta
Time the record covers
At least 5.6 million years on record.
The record covers at least 61.66 Mya to 56 Mya. No occurrence read is dated outside 66 Mya to 51.1 Mya.
13 occurrences of Isoetites horridus on record, most of them in the Paleocene. 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
13 occurrencesThese 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
9 formations
- Golden Valley Formation4
- Fort Union Formation2
- Willwood Formation1
- Ravenscrag Formation1
- Raton Formation1
- Ferris Formation1
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The named rock units Isoetites horridus has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Isoetites horridus and its relatives
PaleoceneWhere Isoetites horridus and its relatives were recorded in the Paleocene.
Found in the same rock
50 taxa- Averrhoites affinis4 sites
- Salvinia preauriculata4 sites
- Ampelopsis acerifolia3 sites
- Cercidiphyllum3 sites
- Dombeya novimundi2 sites
- Eucommia2 sites
- Hydromystria expansa2 sites
- Meliosma longifolia2 sites
- Metasequoia occidentalis2 sites
- Sparganium stygium2 sites
- Trapa angulata2 sites
- Animalia1 site
- Asplenium magnum1 site
- Beringiaphyllum cupanioides1 site
- Cercidiphyllum genetrix1 site
- Chaetoptelea microphylla1 site
- Cornophyllum1 site
- Dicotylophyllum anomalum1 site
- Dicotylophyllum hamameloides1 site
- Dicotylophyllum hebronensis1 site
- Dicotylophyllum trilobum1 site
- Equisetum1 site
- Fortuna1 site
- Fraxinus eocenica1 site
The Paleobiology Database records 13 sites for Isoetites horridus, 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
4 references- Paleocene flora of the Rocky Mountains and Great Plains7
- Stratigraphy and paleobotany of the Golden Valley Formation (Early Tertiary) of western North Dakota4
- Plant and mammal diversity in the Paleocene to Early Eocene of the Bighorn Basin1
- Flora of the Ravenscrag Formation (Paleocene), Southwestern Saskatchewan, Canada1
Each of the 13 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. 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 Isoetites horridus
- Source
- iDigBio
- Credit
- via iDigBio
- Licence
- CC0
- Commercial use
- the licence allows it
No 3D scan of Isoetites horridus was found in Sketchfab.
Smithsonian Open Access and MorphoSource were not reached for this taxon, so this list is what the others held rather than everything there is.
This is what the site found, which is not the same as what exists.
Keep going
What may have been alongside itIsoetites through timeFormations of the PaleoceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. (Dawson 1883)