Egg fossils are the

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

ized remains of eggs laid by

ancient Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history cov ...

animal Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage ...

s. As evidence of the

physiological Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemica ...

processes of an animal, egg fossils are considered a type of

trace fossil A trace fossil, also known as an ichnofossil (; from el, ἴχνος ''ikhnos'' "trace, track"), is a fossil record of biological activity but not the preserved remains of the plant or animal itself. Trace fossils contrast with body fossils, ...

. Under rare circumstances a fossil egg may preserve the remains of the once- developing

embryo An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

inside, in which case it also contains body fossils. A wide variety of different animal groups laid eggs that are now preserved in the fossil record beginning in the

Paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ...

. Examples include

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chorda ...

s like

ammonoids Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

as well as

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with ...

s like fishes, possible

amphibian Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbo ...

s, and

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates ( lizards and snakes) and rhynchocephalia ...

s. The latter group includes the many

dinosaur egg Dinosaur eggs are the organic vessels in which a dinosaur embryo develops. When the first scientifically documented remains of non-avian dinosaurs were being described in England during the 1820s, it was presumed that dinosaurs had laid eggs be ...

s that have been recovered from

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ...

strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as e ...

. Since the organism responsible for laying any given egg fossil is frequently unknown, scientists classify eggs using a parallel system of taxonomy separate from but modeled after the

Linnaean system Linnaean taxonomy can mean either of two related concepts: # The particular form of biological classification (taxonomy) set up by Carl Linnaeus, as set forth in his ''Systema Naturae'' (1735) and subsequent works. In the taxonomy of Linnaeus t ...

. This "

parataxonomy Parataxonomy is a system of labor division for use in biodiversity research, in which the rough sorting tasks of specimen collection, field identification, documentation and preservation are conducted by primarily local, less specialized individu ...

" is called ''veterovata''.

History

The first named oospecies was '' Oolithes bathonicae'', a name given provisionally by Professor J. Buckman to a group of eggs which Buckman believed were laid by a

teleosaur Teleosauridae is a family of extinct typically marine crocodylomorphs similar to the modern gharial that lived during the Jurassic period. Teleosaurids were thalattosuchians closely related to the fully aquatic metriorhynchoids, but were less a ...

. However, modern scientists no longer think it is possible to determine what kind of reptile laid these eggs. In 1859, the first scientifically documented dinosaur egg fossils were discovered in southern France by a Catholic

priest A priest is a religious leader authorized to perform the sacred rituals of a religion, especially as a mediatory agent between humans and one or more deities. They also have the authority or power to administer religious rites; in partic ...

and amateur naturalist named Father

Jean-Jacques Poech Jean-Jacques is a French name, equivalent to "John James" in English. Since the second half of 18th century, Jean Jacques Rousseau was widely known as Jean Jacques. Notable people bearing this name include: Given name * Jean-Jacques Annaud (born 19 ...

, however he thought they were laid by giant birds. The first scientifically ''recognized'' dinosaur egg fossils were discovered

serendipitously Serendipity is an unplanned fortunate discovery. Serendipity is a common occurrence throughout the history of product invention and scientific discovery. Etymology The first noted use of "serendipity" was by Horace Walpole on 28 January 1754. I ...

in 1923 by an

American Museum of Natural History The American Museum of Natural History (abbreviated as AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. In Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 26 int ...

crew while looking for evidence of

early humans ''Homo'' () is the genus that emerged in the (otherwise extinct) genus ''Australopithecus'' that encompasses the extant species ''Homo sapiens'' (modern humans), plus several extinct species classified as either ancestral to or closely relate ...

in Mongolia. Egg discoveries continued to mount all over the world, leading to the development of multiple competing classification schemes. In 1975 Chinese paleontologist

Zhao Zi-Kui Zhao may refer to: * Zhao (surname) (赵), a Chinese surname ** commonly spelled Chao in Taiwan or up until the early 20th century in other regions ** Chiu, from the Cantonese pronunciation ** Cho (Korean surname), represent the Hanja 趙 (Chines ...

started a revolution in fossil egg classification by developing a system of "

" based on the traditional Linnaean system to classify eggs based on their physical qualities rather than their hypothesized mothers. Zhao's new method of egg classification was hindered from adoption by Western scientists due to language barriers. However, in the early 1990s Russian paleontologist Konstantin Mikhailov brought attention to Zhao's work in the English language

scientific literature : ''For a broader class of literature, see Academic publishing.'' Scientific literature comprises scholarly publications that report original empirical and theoretical work in the natural and social sciences. Within an academic field, scie ...

Diversity

Invertebrates

Eggs laid by invertebrate animals are known from the fossil record. Among these are eggs laid by ancient

cephalopods A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, a ...

. Eggs laid by

are the best known cephalopod egg fossils. The best preserved fossil ammonite eggs were preserved in the

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

Kimmeridge Clay The Kimmeridge Clay is a sedimentary deposit of fossiliferous marine clay which is of Late Jurassic to lowermost Cretaceous age and occurs in southern and eastern England and in the North Sea. This rock formation is the major source rock for Nor ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

. Nevertheless, the

fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

of cephalopod eggs is scant since their soft, gelatinous eggs decompose quickly and have little chance to fossilize. Another major group of Mesozoic cephalopods, the

belemnoid Belemnoids are an extinct group of marine cephalopod, very similar in many ways to the modern squid and closely related to the modern cuttlefish. Like them, the belemnoids possessed an ink sac, but, unlike the squid, they possessed ten arms of ...

s, have no documented eggs in the fossil record whatsoever, although this may be because scientists have not properly searched for them rather than an actual absence from the fossil record.

Fishes and amphibians

Fossil fish eggs have an extensive record going at least as far back as the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, wh ...

and spanning into the

Cenozoic era The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configu ...

. The eggs of many different fish

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

have contributed to this record, including

lobe-finned fish Sarcopterygii (; ) — sometimes considered synonymous with Crossopterygii () — is a taxon (traditionally a class or subclass) of the bony fishes known as the lobe-finned fishes. The group Tetrapoda, a mostly terrestrial superclass includ ...

, placoderms, and

sharks Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorp ...

. Occasionally eggs are preserved still within the mother's body, or associated with fossil

embryos An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

. Some fossil eggs possibly laid by fish cannot be confidently distinguished from those laid by

amphibians Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbo ...

. Several fossilized fish or amphibian eggs have been classified as ichnogenera, including '' Mazonova'', '' Archaeoovulus'', '' Chimaerotheca'', '' Fayolia'', and '' Vetacapsula''.

Reptiles

The fossil record of reptile eggs goes back at least as far as the

Early Permian 01 or '01 may refer to: * The year 2001, or any year ending with 01 * The month of January * 1 (number) Music * 01'' (Richard Müller album), 2001 * ''01'' (Son of Dave album), 2000 * ''01'' (Urban Zakapa album), 2011 * ''O1'' (Hiroyuki Sawan ...

. However, since the earliest reptile eggs probably had soft shells with little preservation potential, reptilian eggs may go back significantly farther than their fossil record. Many ancient reptile groups are known from egg fossils including

crocodilia Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period ( Cenomanian stage) and are the closest livi ...

ns,

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

s, and turtles. Some ancient reptiles, like ichthyosaursEllis, Richard, (2003) ''Sea Dragons - Predators of the Prehistoric Oceans''. University Press of Kansas. . and plesiosaurs are known to have given live birth and are therefore not anticipated to have left behind egg fossils. Dinosaur eggs are among the most well known kind of fossil reptile eggs.

Classification

Fossil eggs are classified according to the parataxonomic system called Veterovata. There are three broad categories in the scheme, on the pattern of organismal phylogenetic classification, called oofamilies, oogenera and oospecies (collectively known as ootaxa).Olga Amo, Gloria Cuenca–Bescós & José Ignacio Canudo (1999). José Ignacio Canudo & Gloria Cuenca-Bescós, ed. "Vertebrate eggshell fragments from the Lower Cretaceous (Lower Barremian) of Camino Canales (Galve Bassin, Province of Teruel, NE Spain)" (PDF). IV European Workshop on Vertebrate Palaeontology. Albarracín, Spain: Universidad de Zaragoza. The names of oogenera and oofamilies conventionally contain the root "oolithus" meaning "stone egg", but this rule is not always followed. They are divided up into several basic types: Testudoid, Geckoid, Crocodiloid, Dinosauroid-spherulitic, Dinosauroid-prismatic, and Ornithoid. Veterovata does not always mirror the taxonomy of the animals which laid the eggs.Carpenter, Kenneth (1999). ''Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past)'', Indiana University Press; .

Parataxonomy

The oogenus level parataxonomy of Veterovata, following Lawver and Jackson (2014) for Testudoid, Hirsch (1996) for Geckonoid eggs, and Mikhailov et al. (1996) for the rest unless otherwise noted: Testudoid * ''Spheruflexibilis'' morphotype ** Oofamily Testudoflexoolithidae *** '' Testudoflexoolithus'' * ''Spherurigidis'' morphotype ** Oofamily Testudoolithidae *** '' Testudoolithus'' *** '' Emydoolithus'' *** '' Haininchelys'' *** '' Chelonoolithus'' Geckonoid * Geckonoid morphotype ** Oofamily

Gekkoolithidae ''Gekkoolithus'' is an oogenus of fossil gecko egg. Unfortunately, gecko eggs have not been well-studied, and their fossils are very rare, making classification of them difficult. ''Gekkolithus'' eggs are very similar to those of the modern '' Ph ...

*** '' Gekkoolithus'' *** '' Gekkonidovum'' Crocodiloid * Oogenus

Mycomorphoolithus ''Mycomorphoolithus'' (meaning "fungus-shaped stone egg") is an oogenus of fossil eggs found in Spain and England. They possibly represent eggshells of non-eusuchian Crocodylomorpha, crocodylomorphs, and are similar to, but not part of, the Krokol ...

* Oofamily

Krokolithidae Krokolithidae is an oofamily of fossil crocodylomorph eggs. The oogenus ''Mycomorphoolithus ''Mycomorphoolithus'' (meaning "fungus-shaped stone egg") is an oogenus of fossil eggs found in Spain and England. They possibly represent eggshells of ...

** '' Bauruoolithus'' ** ''

Krokolithes ''Krokolithes'' is an oogenus of Crocodiloid eggs. These eggs were laid by an extinct species of Crocodylian. It contains three oospecies: ''K. dinophilus'', ''K. wilsoni'' and ''K. helleri''. 1 Fossils of the oogenus have been found in the Oligo ...

'' ** '' Suchoolithus'' Mosasauroid * '' Antarcticoolithus'' Dinosauroid-spherulitic * '' Placoolithus'' * '' Sphaerovum'' * '' Stromatoolithus'' * '' Tacuarembovum'' * Oofamily Cairanoolithidae ** '' Cairanoolithus''Sellés, A. G., & Galobart, À. (2015). Reassessing the endemic European Upper Cretaceous dinosaur egg Cairanoolithus. Historical Biology, (ahead-of-print), 1-14. * Oofamily

Stalicoolithidae Stalicoolithidae is an oofamily Egg fossils are the fossilized remains of eggs laid by ancient animals. As evidence of the physiological processes of an animal, egg fossils are considered a type of trace fossil. Under rare circumstances a foss ...

** '' Coralloidoolithus'' ** '' Shixingoolithus'' ** '' Stalicoolithus'' * Oofamily Spheroolithidae Oolithes spheroides (Senckenberg)

** '' Guegoolithus'' ** '' Spheroolithus'' ** ''

Paraspheroolithus ''Spheroolithus'' is an oogenus of dinosaur egg.Wang Q, Wang X L, Zhao Z K, and Jiang Y G. (2012).A new oofamily of dinosaur egg from the Upper Cretaceous of Tiantai Basin, Zhejiang Province, and its mechanism of eggshell formation Chinese Scien ...

'' * Oofamily Phaceloolithidae ** '' Phaceloolithus'' * Oofamily Ovaloolithidae ** '' Ovaloolithus'' * Oofamily Megaloolithidae ** '' Megaloolithus'' ** '' Pseudomegaloolithus'' * Oofamily

Similifaveoloolithidae ''Similifaveoloolithus'' is an oogenus of fossil dinosaur egg from the Tiantai basin in Zhejiang Province, China. It is the sole known oospecies of the oofamily Similifaveoloolithidae.Wang Qiang, Zhao Zikui, Wang Xiaolin, Zhang Shukang, and Jian ...

** '' Similifaveoloolithus'' * Oofamily

Faveoloolithidae Faveoloolithidae is an oofamily of dinosaur eggs. It contains '' Faveoloolithus'', '' Hemifaveoloolithus'', '' Parafaveoloolithus'', and probably '' Sphaerovum''. However, unlike the other Faveoloolthids, ''Sphaerovum'' has compactituberculate o ...

** '' Faveoloolithus'' ** '' Hemifaveoloolithus'' ** '' Parafaveoloolithus'' * Oofamily Youngoolithidae ** '' Youngoolithus'' * Oofamily Dendroolithidae ** '' Dendroolithus'' * Oofamily Dictyoolithidae ** '' Dictyoolithus'' ** '' Paradictyoolithus'' ** '' Protodictyoolithus'' * Oofamily Polyclonoolithidae ** ''

Polyclonoolithus ''Polyclonoolithus'' is an oogenus of fossil dinosaur egg. It is from the Early Cretaceous of Gansu, China. They have distinctive, branching eggshell units, which may represent the original form of spheroolithids. Distribution ''Polyclonoolit ...

''Xie, J.-F., Zhang, S.-K., Jin, X.-S., Li, D.-Q., and Zhou, L.-Q. (2016)
A new type of dinosaur eggs from Early Cretaceous of Gansu Province, China.
" ''Vertebrata PalAsiatica'', 54(1):1-10. Dinosauroid-prismatic * '' Pseudogeckoolithus'' * Oofamily Arriagadoolithidae ** '' Arriagadoolithus'' ** '' Triprismatoolithus'' * Oofamily

Prismatoolithidae Prismatoolithidae is an oofamily of fossil eggs. They may have been laid by ornithopods or theropod Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on ea ...

** '' Preprismatoolithus'' ** '' Prismatoolithus'' ** '' Protoceratopsidovum'' ** ''

Sankofa (pronounced ''SAHN''-koh-fah) is a word in the Twi language of Ghana meaning “to retrieve" (literally "go back and get"; - to return; - to go; - to fetch, to seek and take) and also refers to the Bono Adinkra symbol represented either ...

'' ** '' Spheruprismatoolithus''E. S. Bray. 1999. Eggs and eggshell from the Upper Cretaceous North Horn Formation, central Utah. In D. D. Gillette (ed.), Vertebrate Paleontology in Utah, Utah Geological Survey Miscellaneous Publication 99-1:361-375 ** ''

Trigonoolithus ''Trigonoolithus'' is an oogenus of dinosaur egg, representing a basal prismatoolithid. Its eggshell, like avian eggs, is composed of three structural layers, but cladistic analysis suggests that its parent was a non-avian theropod. History Foss ...

'' Ornithoid * Ornithoid-ratite Morphotype ** '' Ageroolithus'' ** '' Diamantornis'' ** '' Ornitholithus'' ** '' Reticuloolithus''D. K. Zelenitsky and W. J. Sloboda. 2005. Eggshells. In P. J. Currie and E. B. Koppelhus (eds.), Dinosaur Provincial Park: A Spectacular Ancient Ecosystem Revealed. Indiana University Press, Bloomington 398-404 ** '' Struthiolithus'' ** '' Tristraguloolithus'' ** '' Tubercuoolithus'' ** Oofamily

Elongatoolithidae Elongatoolithidae is an oofamily of fossil eggs, representing the eggs of oviraptorosaurs (with the exception of the Bird, avian ''Ornitholithus''). They are known for their highly elongated shape. Elongatoolithids have been found in Europe, Asia, ...

*** '' Continuoolithus'' *** '' Ellipsoolithus'' *** '' Elongatoolithus'' Dendroolithus-eggs

*** '' Heishanoolithus'' *** ''

Macroelongatoolithus ''Macroelongatoolithus'' is an oogenus of large theropod dinosaur eggs, representing the eggs of giant caenagnathid oviraptorosaurs. They are known from Asia and from North America. Historically, several oospecies have been assigned to ''Macroelo ...

'' *** '' Macroolithus'' *** '' Nanhsiungoolithus'' *** '' Paraelongatoolithus'' *** ''

Porituberoolithus ''Porituberoolithus'' is an oogenus of dinosaur egg found in the late Campanian Oldman Formation and Dinosaur Park Formation of Alberta, the Fossil Forest Member of the Fruitland Formation in New Mexico, the Upper Shale Member of the Aguja Fo ...

'' *** ''

Rodolphoolithus ''Rodolphoolithus'' is an oogenus of Elongatoolithidae, elongatoolithid egg native to Morocco. It is known only from a single partial egg and several eggshell fragments, but it probably had a highly elongated shape like other Elongatoolithids. The ...

'' *** '' Spongioolithus'' *** '' Trachoolithus'' *** '' Undulatoolithus'' ** Oofamily

Laevisoolithidae Laevisoolithidae is an oofamily of fossil eggs belonging to the Ornithoid-ratite morphotype. Their eggshells are smooth and very thin, typically less than a millimeter thick. Laevisoolithids may be the eggs of Enantiornithid birds.K. E. Mikhail ...

*** ''

Laevisoolithus ''Laevisoolithus'' is an oogenus of fossil egg. Its sole oospecies, ''L. sochavai,'' is native to the Nemegt Formation in Mongolia. ''Laevisoolithus'' is characterized by its thin, smooth eggshells. These eggs were probably laid by a bird or a sma ...

'' *** ''

Subtiliolithus ''Subtiliolithus'' is an oogenus of fossil egg from the Nemegt Formation of Mongolia and the Ohyamashimo Formation of Japan. The eggs are notable for a very thin eggshell. It contains three oospecies: ''S. hyogoensis'', ''S. kachchhensis'' and ' ...

'' *** ''

Tipoolithus ''Tipoolithus'' is an oogenus of fossil egg native to the Irbzer Formation in Morocco. Its classification is uncertain, but it most closely resembles Laevisoolithids, and like members of that oofamily, it was laid by an enantiornithine bird or ...

''Garcia, G., T. Rodolphe, H. Cappetta, B. Marandat, I. Bentaleb, A. Benabdallah and M. Vianey-Liaud. (2003). "First Record of Dinosaur Eggshels and Teeth from The North-West African Maastrichtian (Morocco)." ''Palaeovertebrata'', Montpellier, 32 (2-4): 59-69, ** Oofamily Medioolithidae *** '' Incognitoolithus'' *** '' Microolithus'' *** '' Mediolithus'' ** Oofamily Montanoolithidae *** '' Montanoolithus'' ** Oofamily

Oblongoolithidae ''Oblongoolithus'' is an oogenus of dinosaur eggs, from the Campanian Barun Goyot Formation of Mongolia. The oogenus contains one oospecies ''O. glaber''. *** ''

Oblongoolithus ''Oblongoolithus'' is an oogenus of dinosaur eggs, from the Campanian Barun Goyot Formation of Mongolia. The oogenus contains one oospecies ''O. glaber''. * Ornithoid-prismatic Morphotype ** '' Dispersituberoolithus'' ** Oofamily Gobioolithidae *** '' Gobioolithus'' ''

Incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertain ...

/Unclassified'' * ''

Oolithes ''Oolithes'' is an oogenus with uncertain affinities. It has historical significance because it was the earliest named oogenus. James Buckman described the first named species as ''Oolithes bathonicae'' in a communication to the 4 May 1859 meet ...

'' * '' Metoolithus'' * ''

Mosaicoolithus ''Mosaicoolithus'' is an oogenus of fossil egg from the Cenomanian Chichengshan Formation ( Tiantai Group) and Albian to Cenomanian Laijia Formation ( Qujiang Group) of Tiantai County, Zhejiang Province Zhejiang ( or , ; , Chinese postal ...

'' * ''

'' * '' Nipponoolithus'' * ''

Parvoblongoolithus ''Parvoblongoolithus'' is an oogenus of fossil dinosaur egg whose small size and unusual shape suggest the possibility that it is a cock egg, dwarf egg. Distribution The sole known ''Parvoblongoolithus jinguoensis'' specimen was found in the Uppe ...

'' * '' Parvoolithus''Mikhailov, K.E. (1997). Fossil and recent eggshell in amniotic vertebrates: Fine structure, comparative morphology and classification. Special Papers in Palaeontology 56. The Palaeontological Association. London. (page 58). * '' Plagioolithus'' * '' Styloolithus'' * Oofamily Pachycorioolithidae ** ''

Pachycorioolithus ''Pachycorioolithus'' is an oogenus of small, thin-shelled fossil egg from the early Cretaceous in China. It probably belongs to a bird, though there is a possibility the parent was a non-avian theropod. It was named in 2016, based on a single ...

References

External links

UCMP's online fossil egg exhibit

Paleofile
{{Authority control

History

Diversity

Invertebrates

Fishes and amphibians

Reptiles

Classification

Parataxonomy

See also

References

External links