Omnisaura

Egg type

Subtiliolithus

Mikhailov 1991

Subtiliolithus is an egg type: the name is for the fossil eggs themselves. The animal that laid them is not known for certain. Its eggs are found in rocks 113.2–66 million years old in India, Japan and Mongolia.

Confidence labels
How sure are we?0 high10 medium2 lowHow we rate confidence

Confidence labels are switched off. Facts with low confidence, or where sources disagree, still carry a small dot: tap it for the reason.

At a glance

Data as of 11 October 2026
113.2–66 Ma
Triassic
Jurassic
Cretaceous
252 million years ago20114366

The last non-bird dinosaurs died out 66 million years ago. That's as far from us as the end of this bar.

Named by
Mikhailov 1991
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Described in
K. E. Mikhailov (1991). Classification of fossil eggshells of amniotic vertebrates. Acta Palaeontologica Polonica 36(2): 193–238.
mediummedium: Only PBDB gives this; its author and year match the naming authority (Mikhailov 1991).
Sources

Given by: Paleobiology Database. The publication the Paleobiology Database gives as the authority for this genus name, usually the one that first named and described it.

Type species
Subtiliolithus microtuberculatus
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Dated to
Albian to Maastrichtian, 113.2–66 million years ago
mediummedium: Only PBDB gives this; nothing contradicts it.
Omnisaura calculation113.2–66 million years ago, from its dated fossil records
mediummedium: Omnisaura's calculation from 5 confirmed PBDB records.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Found in
India
mediummedium: Only PBDB records it (2 records).
Japan
mediummedium: Only PBDB records it (2 records).
Mongolia
lowlow: Only one PBDB record.
mixedmixed: Levels differ between entries; each has its own.
Sources

Given by: Paleobiology Database. How it was chosen: Union of all sources (ISO 3166).

Rock formations
Ohyamashimo
mediummedium: Only PBDB records it (2 records).
Nemegt
lowlow: Only one PBDB record.
mixedmixed: Levels differ between entries; each has its own.
Sources

Given by: Paleobiology Database. How it was chosen: Canonical names, automatic and editor-approved matches applied.

Egg family
Laevisoolithidae
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Parent group
Laevisoolithidae
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Species named in its records
Subtiliolithus hyogoensis, Subtiliolithus kachchhensis, Subtiliolithus microtuberculatus
Sources

Given by: Paleobiology Database (the species its fossil records are identified as).

Known from
Eggs
Sources

Given by: Paleobiology Database (what the name was based on).

Laid by
Not known for certain. Eggs rarely show which animal laid them.
Sources: Paleobiology Database (CC BY 4.0), Natural History Museum Data Portal (CC0 1.0)Confidence levels and gaps are Omnisaura's own assessment.

Gaps are answers

What isn't known yet

  • The animal that laid them: not known for certain, as for most egg types.
  • Order: no source we use gives it yet.
  • Common names: no source we use gives it yet.
  • What it was named after: no source we use gives it yet.
  • Resting on one source: 6 facts come from a single source with nothing against them (rated medium): name (PBDB); authority (PBDB); type species (PBDB); parent group (PBDB); family (PBDB); age (headline) (PBDB).

Size and appearance aren't covered yet, and diet and way of life only as PBDB infers them for the wider group. Omnisaura leaves the rest out rather than guess.

Where sources disagree

None open. Where our sources overlap, they agree on everything shown here.

Did it meet…?

?

Same time, different places. Their fossils overlap in age, 83.6 to 66 million years ago, but no rock formation holds both.

Going by the ages and rock formations of their dated fossils, as on the map. Compare their fossil sites on the map.

Connections

Genera linked to Subtiliolithus by where and when their fossils were found, by classification and by who named them. Select a name to open its page.

SubtiliolithusFound in the same rocksSame naming authorAlso found in IndiaTarbosaurusSaurolophusGallimimusAvimimusand 27 moreMegaloolithusProtoceratopsidovumTrachoolithusFusioolithusIsisaurusAntarctosaurusIkqaumishanand 5 more

Found in the same rocks 31

Genera and other fossil types from the same rock units, from rocks of overlapping age, the most shared fossil sites first.

TarbosaurusSaurolophusGallimimusAvimimusCoralloidoolithusDeinocheirusElongatoolithusMacroolithusMononykusOksokoPrenocephaleBarsboldiaElmisaurusHomalocephaleOvaloolithusSpheroolithusand 15 more

Named by Mikhailov 3

Genera whose naming authority includes the same surname. The authority has no initials, so different people who share a surname can appear together.

MegaloolithusProtoceratopsidovumTrachoolithus

Found in India 9

Other genera found in India, from rocks of overlapping age, the most fossil sites there first.

MegaloolithusFusioolithusIsisaurusAntarctosaurusIkqaumishanImrankhanheroLaevisuchusPakisaurusQaikshaheen

Credits

Where this page comes from

  • Paleobiology DatabaseCC BY 4.0 · fossil records, ages, classification
  • Natural History Museum Data PortalCC0 1.0 · catalogued specimens
  • OmnisauraOmnisaura editorial · confidence levels and gaps
  • PaleoMAP PaleoCoastlines (Kocsis and Scotese 2021)CC BY 4.0 · ancient coastlines on the small map
  • Natural EarthPublic domain · today's coastlines