Agustinia
Encyclopedia
Agustinia is a genus
of sauropod dinosaur
from the Early Cretaceous
Period of South America
. Like all known sauropods, it was quadrupedal and herbivorous. Although some sauropods are known to have body armor
, Agustinias armor was unique even among sauropods. It had a series of wide, vertical spikes and plates down the center of its back, somewhat like the unrelated Stegosaurus
. Aside from the armor, very little is known about the anatomy
of Agustinia. A fibula (lower leg bone) has been recovered that is about 3 feet (895 mm) long. When compared to the same bone in related dinosaurs, this indicates that Agustinia may have been about 50 feet (15 meters) long.
The name Agustinia honors the discoverer of the specimen, Agustin Martinelli. This dinosaur was originally named in a 1998 abstract
written by famous Argentine
paleontologist Jose Bonaparte
. The original generic name was Augustia, which, as it turned out, was already preoccupied
by a beetle
(see also: Megapnosaurus
, Protognathosaurus
). Bonaparte changed the name to Agustinia in a full paper published in 1999, which also introduced the family Agustiniidae. There is one named species
(A. ligabuei), which is named in honor of Dr. Giancarlo Ligabue, a philanthropist
who provided financial support to the expedition which recovered the remains.
Agustinia was recovered from the Lohan Cura Formation
of Neuquen Province
in Argentina
, which is thought to date from the late Aptian
to Albian
stages of the Early Cretaceous
Period, between 116 and 100 million years ago.
Only fragmentary remains are known. These include fragments of vertebrae from the back, hips, and tail regions of the spinal column, and 9 of the oddly-shaped plates or spikes which were attached to those vertebrae. Parts of the lower hind limb were also recovered: a fibula, tibia
, and 5 metatarsals. A femur
(thigh bone) was found at the site but was too fragmented to collect.
Because of its unusual features, Agustinia was originally assigned to its own family, Agustiniidae (Bonaparte, 1999). This family name has not come into wide acceptance. Agustinia is difficult to classify because of its fragmentary nature, and because it exhibits features of both diplodocoid
and titanosaurian sauropods. Both groups are known in Early Cretaceous Argentina, so Agustinia most likely belongs to one or the other, but until more complete remains are found, it will be hard to know which one.
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 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 Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...
Period of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. Like all known sauropods, it was quadrupedal and herbivorous. Although some sauropods are known to have body armor
Armour (zoology)
Armour in animals is external or superficial protection against attack by predators, formed as part of the body , usually through the hardening of body tissues, outgrowths or secretions. It has therefore mostly developed in 'prey' species...
, Agustinias armor was unique even among sauropods. It had a series of wide, vertical spikes and plates down the center of its back, somewhat like the unrelated Stegosaurus
Stegosaurus
Stegosaurus is a genus of armored stegosaurid dinosaur. They lived during the Late Jurassic period , some 155 to 150 million years ago in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well...
. Aside from the armor, very little is known about the anatomy
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
of Agustinia. A fibula (lower leg bone) has been recovered that is about 3 feet (895 mm) long. When compared to the same bone in related dinosaurs, this indicates that Agustinia may have been about 50 feet (15 meters) long.
The name Agustinia honors the discoverer of the specimen, Agustin Martinelli. This dinosaur was originally named in a 1998 abstract
Abstract (summary)
An abstract is a brief summary of a research article, thesis, review, conference proceeding or any in-depth analysis of a particular subject or discipline, and is often used to help the reader quickly ascertain the paper's purpose. When used, an abstract always appears at the beginning of a...
written by famous Argentine
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
paleontologist Jose Bonaparte
José Bonaparte
José Fernando Bonaparte, Ph.D. , is an Argentine paleontologist who discovered a plethora of South American dinosaurs and mentored a new generation of Argentine paleontologists like Rodolfo Coria...
. The original generic name was Augustia, which, as it turned out, was already preoccupied
International Code of Zoological Nomenclature
The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...
by a beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
(see also: Megapnosaurus
Megapnosaurus
Megapnosaurus was a dinosaur of the theropod family Coelophysidae, formerly called Syntarsus , living during the Early Jurassic. It was renamed by American entomologist Dr. Michael Ivie , Polish Australian Dr...
, Protognathosaurus
Protognathosaurus
Protognathosaurus is a genus of dinosaur from the Middle Jurassic. It was a sauropod found in what is present-day China. The type species, P. oxyodon, was originally described by Zhang , and was renamed by George Olshevsky in 1991...
). Bonaparte changed the name to Agustinia in a full paper published in 1999, which also introduced the family Agustiniidae. There is one named species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
(A. ligabuei), which is named in honor of Dr. Giancarlo Ligabue, a philanthropist
Philanthropist
A philanthropist is someone who engages in philanthropy; that is, someone who donates his or her time, money, and/or reputation to charitable causes...
who provided financial support to the expedition which recovered the remains.
Agustinia was recovered from the Lohan Cura Formation
Lohan Cura Formation
The Lohan Cura Formation is a geologic formation with outcrops in the Argentine provinces of Río Negro, Neuquén, and Mendoza. It is the second oldest Cretaceous terrestrial formation in the Neuquén Basin....
of Neuquen Province
Neuquén Province
Neuquén is a province of Argentina, located in the west of the country, at the northern end of Patagonia. It borders Mendoza Province to the north, Rio Negro Province to the southeast, and Chile to the west...
in Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, which is thought to date from the late Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
to 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...
stages of the Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...
Period, between 116 and 100 million years ago.
Only fragmentary remains are known. These include fragments of vertebrae from the back, hips, and tail regions of the spinal column, and 9 of the oddly-shaped plates or spikes which were attached to those vertebrae. Parts of the lower hind limb were also recovered: a fibula, tibia
Tibia
The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
, and 5 metatarsals. A femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
(thigh bone) was found at the site but was too fragmented to collect.
Because of its unusual features, Agustinia was originally assigned to its own family, Agustiniidae (Bonaparte, 1999). This family name has not come into wide acceptance. Agustinia is difficult to classify because of its fragmentary nature, and because it exhibits features of both diplodocoid
Diplodocoidea
Diplodocoidea was a superfamily of sauropod dinosaurs, which included some of the longest animals of all time, including slender giants like Supersaurus, Diplodocus, Apatosaurus, and Amphicoelias...
and titanosaurian sauropods. Both groups are known in Early Cretaceous Argentina, so Agustinia most likely belongs to one or the other, but until more complete remains are found, it will be hard to know which one.
External links
- Agustinia at Dinodata