Lapparentosaurus
Encyclopedia
Lapparentosaurus is a genus
of macronarian
sauropod dinosaur
from the Middle Jurassic
. Its fossil
s were found in Madagascar
.
In 1895 Richard Lydekker
named a new species of Bothriospondylus
, B. madagascariensis based on fossils found before 1894 by J.T. Last in the Majunga Basin in layers of the Bathonian
, the Isalo III Formation
. Because there was no real connection with this English form, in 1986 José Fernando Bonaparte named a separate genus. The type species
, the only known, is Lapparentosaurus madagascariensis. The generic name honours Albert-Félix de Lapparent
. The holotype
assigned by Bonaparte, MAA 91-92, consists of two neural arches. Much more abundant material has been referred, from at least three but perhaps as much as ten individuals from different growth stages. This includes vertebrae and limb elements but no skulls. The species is still lacking a good description and diagnosis. It should not be confused with ?Bothriospondylus madagascariensis, a distinct taxon.
Age determination
studies performed using growth ring counts suggest that the longevity of this sauropod was 43 years, and that it was a fast-growing endotherm
.
Though sometimes considered a brachiosaurid, cladistic analyses showed Lapparentosaurus to be a basal member of Macronaria
or Titanosauriformes.
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 macronarian
Macronaria
Macronaria is a clade of sauropod dinosaurs from the Middle Jurassic to Late Cretaceous Periods of what are now North America, South America, Europe, Asia and Africa. The name means 'large nostrils' , in reference to the large nasal openings high on the head that probably supported fleshy...
sauropod 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 Middle Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
. Its fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s were found in Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
.
In 1895 Richard Lydekker
Richard Lydekker
Richard Lydekker was an English naturalist, geologist and writer of numerous books on natural history.-Biography:...
named a new species of Bothriospondylus
Bothriospondylus
Bothriospondylus is an dubious genus of sauropod dinosaur. It lived during the Late Jurassic.The type species, Bothriospondylus suffossus, was described by Richard Owen in 1875. The specific epithet suffossus means "undermined" in Latin, a reference to the fact that pleurocoels had hollowed out...
, B. madagascariensis based on fossils found before 1894 by J.T. Last in the Majunga Basin in layers of the Bathonian
Bathonian
In the geologic timescale the Bathonian is an age or stage of the Middle Jurassic. It lasted from approximately 167.7 Ma to around 164.7 Ma...
, the Isalo III Formation
Isalo III Formation
The Isalo III Formation is a geological formation in Africa. It dates back to the Middle Jurassic.-Vertebrate fauna:...
. Because there was no real connection with this English form, in 1986 José Fernando Bonaparte named a separate genus. 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...
, the only known, is Lapparentosaurus madagascariensis. The generic name honours Albert-Félix de Lapparent
Albert-Félix de Lapparent
Albert-Félix de Lapparent was a French palaeontologist. He was also a Sulpician priest. He undertook a number of fossil-hunting explorations in the Sahara desert. He contributed greatly to our knowledge of dinosaurs and other prehistoric creatures...
. 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...
assigned by Bonaparte, MAA 91-92, consists of two neural arches. Much more abundant material has been referred, from at least three but perhaps as much as ten individuals from different growth stages. This includes vertebrae and limb elements but no skulls. The species is still lacking a good description and diagnosis. It should not be confused with ?Bothriospondylus madagascariensis, a distinct taxon.
Age determination
Age determination of dinosaurs
Age determination in dinosaurs is mainly used to determine the approximate age of a dinosaur when the animal died.-History:Early attempts to estimate the longevity of dinosaurs used allometric scaling principles. Ages were determined by dividing individual mass estimates by rates of growth for...
studies performed using growth ring counts suggest that the longevity of this sauropod was 43 years, and that it was a fast-growing endotherm
Endotherm
An endotherm is an organism that produces heat through internal means, such as muscle shivering or increasing its metabolism...
.
Though sometimes considered a brachiosaurid, cladistic analyses showed Lapparentosaurus to be a basal member of Macronaria
Macronaria
Macronaria is a clade of sauropod dinosaurs from the Middle Jurassic to Late Cretaceous Periods of what are now North America, South America, Europe, Asia and Africa. The name means 'large nostrils' , in reference to the large nasal openings high on the head that probably supported fleshy...
or Titanosauriformes.