Eolambia
Encyclopedia
Eolambia is a genus
of herbivorous iguanodont
ian dinosaur
from the mid-Cretaceous
Period of the USA
.
In 1992 Carole Jones and her husband Ramal Jones near Castle Dale in Emery County, Utah
, on the San Rafael Swell Anticline discovered a fossil site which would be named the Carol Quarry (sic
) in her honour. Among the fossils were the remains of a euornithopod reported upon by James Ian Kirkland in 1994. Based on these fossils the type species
Eolambia caroljonesa was named by Kirkland in 1998. The generic name comes from the Greek
eos/ἠώς meaning 'dawn' or 'morning', implying 'early'. The Lambia suffix is after Lawrence Lambe
, Canadian
palaeontologist, whose name was given to Lambeosaurus
. In all, the genus name means "dawn (or early) lambeosaurine". The specific name honours Carole Jones. The genus and species were also known informally before publication as "Eohadrosaurus caroljonesi"; the final name was suggested by Michael Skrepnick.
The holotype
specimen, CEUM 9758, was found in the Mussentuchit Member of the Cedar Mountain Formation
, probably dating to the Cenomanian
, about 98.5 million year ago, though earlier estimates gave the age as the late Albian
. It consists of a partial skull. Partial skeletons of adult and juvenile exemplars have been recovered together with eggs and embryos. The paratype
s are CEUM 5212, CEUM 27749 and CEUM 24389. Referred specimens include OMNH 28919, OMNH 28511, OMNH 27749 and OMNH 04202. The finds represent at least eleven individuals and most elements of the skeleton.
The holotype skull has a length of about a metre and Kirkland from this inferred a body length of nine metres. The skull is relatively flat and elongated. Gregory S. Paul
estimated a body length of six metres and a weight of one tonne in 2010.
Kirkland originally assigned Eolambia to the Hadrosauridae, considering it the basal-most member of the Lambeosaurinae
. Later analyses showed that Eolambia was a basal
member of the Hadrosauroidea
, outside of the Hadrosauridae.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of herbivorous iguanodont
Iguanodont
Iguanodonts were herbivorous dinosaurs that lived from the mid-Jurassic to Late Cretaceous. Some members include Camptosaurus, Callovosaurus, Iguanodon, Ouranosaurus, and the hadrosaurids or "duck-billed dinosaurs". Iguanodonts were one of the first groups of dinosaurs to be found...
ian dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
from the mid-Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
Period of the USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
In 1992 Carole Jones and her husband Ramal Jones near Castle Dale in Emery County, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, on the San Rafael Swell Anticline discovered a fossil site which would be named the Carol Quarry (sic
Sic
Sic—generally inside square brackets, [sic], and occasionally parentheses, —when added just after a quote or reprinted text, indicates the passage appears exactly as in the original source...
) in her honour. Among the fossils were the remains of a euornithopod reported upon by James Ian Kirkland in 1994. Based on these fossils the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
Eolambia caroljonesa was named by Kirkland in 1998. The generic name comes from the Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
eos/ἠώς meaning 'dawn' or 'morning', implying 'early'. The Lambia suffix is after Lawrence Lambe
Lawrence Lambe
Lawrence Morris Lambe was a Canadian geologist and palaeontologist from the Geological Survey of Canada .His published work, describing the diverse and plentiful dinosaur discoveries from the fossil beds in Alberta, did much to bring dinosaurs into the public eye and helped usher in the Golden...
, Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
palaeontologist, whose name was given to Lambeosaurus
Lambeosaurus
Lambeosaurus is a genus of hadrosaurid dinosaur that lived about 76 to 75 million years ago, in the Late Cretaceous Period of North America. This bipedal/quadrupedal, herbivorous dinosaur is known for its distinctive hollow cranial crest, which in the best-known species resembled a hatchet...
. In all, the genus name means "dawn (or early) lambeosaurine". The specific name honours Carole Jones. The genus and species were also known informally before publication as "Eohadrosaurus caroljonesi"; the final name was suggested by Michael Skrepnick.
The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
specimen, CEUM 9758, was found in the Mussentuchit Member of the Cedar Mountain Formation
Cedar Mountain Formation
The Cedar Mountain Formation is the name given to distinctive sedimentary rocks in eastern Utah that occur between the underlying Morrison Formation and overlying Naturita Formation . It is composed of non-marine sediments, that is, sediments deposited in rivers, lakes and on flood plains...
, probably dating to the Cenomanian
Cenomanian
The Cenomanian is, in the ICS' geological timescale the oldest or earliest age of the Late Cretaceous epoch or the lowest stage of the Upper Cretaceous series. An age is a unit of geochronology: it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding...
, about 98.5 million year ago, though earlier estimates gave the age as the late Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
. It consists of a partial skull. Partial skeletons of adult and juvenile exemplars have been recovered together with eggs and embryos. The paratype
Paratype
Paratype is a technical term used in the scientific naming of species and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany...
s are CEUM 5212, CEUM 27749 and CEUM 24389. Referred specimens include OMNH 28919, OMNH 28511, OMNH 27749 and OMNH 04202. The finds represent at least eleven individuals and most elements of the skeleton.
The holotype skull has a length of about a metre and Kirkland from this inferred a body length of nine metres. The skull is relatively flat and elongated. Gregory S. Paul
Gregory S. Paul
Gregory Scott Paul is a freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known for his work and research on theropod dinosaurs and his detailed illustrations, both live and skeletal...
estimated a body length of six metres and a weight of one tonne in 2010.
Kirkland originally assigned Eolambia to the Hadrosauridae, considering it the basal-most member of the Lambeosaurinae
Lambeosaurinae
Lambeosaurinae is a group of crested hadrosaurid dinosaurs.-Classification:Lambeosaurines have been split into Parasaurolophini and Corythosaurini . Corythosaurini and Parasaurolophini as terms entered the formal literature in Evans and Reisz's 2007 redescription of Lambeosaurus magnicristatus...
. Later analyses showed that Eolambia was a basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
member of the Hadrosauroidea
Hadrosauroidea
Hadrosauroidea is a clade or superfamily of ornithischian dinosaurs that includes the "duck-billed" dinosaurs, or hadrosaurids, and their close relatives. Many primitive hadrosauroids, such as the sail-backed Ouranosaurus, have traditionally been included in a paraphyletic "Iguanodontidae"...
, outside of the Hadrosauridae.