Cairanoolithus
Cairanoolithus is an oogenus of dinosaur egg which is found in Southwestern Europe. The eggs are large and spherical. Their outer surface is either smooth, or covered with a subdued pattern of ridges interspersed with pits and grooves. Multiple fossil egg clutches are known but the nest structure is unclear.

Ghedoghedo · 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
- CairanoolithidaePBDB
- Diet
- herbivorePBDB, for Ornithischia
- Life habit
- ground dwelling, gregariousPBDB, for Ornithischia
- Motility
- actively mobilePBDB, for Ornithischia
- Environment
- terrestrialPBDB, for Ornithischia
Time the record covers
At most 18 million years on record.
Every occurrence read is dated to somewhere between 83.6 Mya and 66 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.
17 occurrences of Cairanoolithus on record, most of them in the Late Cretaceous. 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
17 occurrences- Late Cretaceous100%
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
5 formations
- Marnes Rouges Inférieures Formation4
- Grès à Reptiles Formation1
- La Posa Formation · Tremp Group1
- Grey Garumnian Formation · Tremp Group1
- Grès de Labarre Formation1
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The named rock units Cairanoolithus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 9 occurrences have no formation on record, which is common for older literature.
Cairanoolithus and its relatives
Late CretaceousWhere Cairanoolithus and its relatives were recorded in the Late Cretaceous.
Found in the same rock
28 taxa- Megaloolithus siruguei7 sites
- Megaloolithus aureliensis5 sites
- Megaloolithus petralta2 sites
- Ornithopoda2 sites
- Testudines2 sites
- Ankylosauria1 site
- Aves1 site
- Crocodylomorpha1 site
- Decapoda1 site
- Elongatoolithidae1 site
- Lirainosaurus astibiae1 site
- Megaloolithus mamillare1 site
- Megaloolithus microtuberculata1 site
- Montanoolithus labadousensis1 site
- Ogresuchus furatus1 site
- Osteichthyes1 site
- Peckichara1 site
- Plantae1 site
- Prismatoolithus matellensis1 site
- Prismatoolithus tenuis1 site
- Rhabdodon priscus1 site
- Selachii1 site
- Septorella brachycera1 site
- Squamata1 site
The Paleobiology Database records 16 sites for Cairanoolithus, 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
8 references- Reassessing the endemic European Upper Cretaceous dinosaur egg Cairanoolithus4
- Dinosaur eggshells from the Late Cretaceous of Laeguedoc (southern France)3
- Review of French dinosaur eggshells: morphology, structure, mineral, and organic composition3
- Organisation des pontes de dinosauriens de la parafamille des Megaloolithidae Zhao, 1979 [Organization of dinosaur clutches of the parafamily Megaloolithidae Zhao, 1979]2
- Late Cretaceous dinosaur eggshells from the Tremp basin, southern Pyrenees, Lleida, Spain2
- Re-evaluation of the age of some dinosaur localities from the southern Pyrenees by means of megaloolithid oospecies1
- Dinosaur eggs in the Upper Cretaceous of the Coll de Nargó area, Lleida Province, south-central Pyrenees, Spain: Oodiversity, biostratigraphy and their implications1
- New cranial remains of titanosaurian sauropod dinosaurs from the Late Cretaceous of Fox-Amphoux-Métisson (Var, SE France)1
Each of the 17 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 Cairanoolithus
- Source
- Wikipedia/Commons
- Credit
- Ghedoghedo
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
No 3D scan of Cairanoolithus 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 itCairanoolithidae through timeFormations of the Late CretaceousThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Vianey-Liaud et al. 1994