Faxinalipterus
Encyclopedia
Faxinalipterus is a genus
of pterosaur
from the Late Triassic
Caturrita Formation
of southern Brazil
.
The type species
, Faxinalipterus minima was named and described in 2010 by José Fernando Bonaparte, Marina Bento Soares and César Leandro Schultz. The generic name is derived from Faxinal do Soturno
and a Latinised Greek pteron, "wing". The specific name, from Latin
minimus, means "smallest".
Fossils of the species have in 2002 and 2005 been found at a site 1.5 kilometres northeast of Faxinal do Sotorno, Rio Grande do Sul
, from the Caturrita Formation dating from the Carnian
-Norian
, 220 - 215 million years old. The holotype
, UFRGS PV0927T, is part of the collection of the Universidade Federal do Rio Grande do Sul and consists of several, partially fragmentary, limb elements, perhaps of a single individual. These do not include bones from the hand. A upper jaw fragment, a left maxilla
with three teeth, has been referred to the species.
Faxinalipterus is a rather small animal, with an estimated total humerus
length of eighteen millimetres. The size has been compared to that of a sparrow
. The hind limbs, much better conserved than the front limbs, are relatively long. From the maxilla it can be inferred that the skull is deep and lightly built with large openings. The maxillary teeth, probably numbering eighteen, are elongated and recurved.
The describers have assigned Faxinalipterus to the Pterosauria, based on its long hollow limbs and saddle-shaped upper joint of the relatively short and robust humerus, suitable to perform a wing stroke. They see it as perhaps the oldest pterosaur known, as it possibly predates European finds from the Norian. That the possible age difference cannot be large, they see as an indication of rapid evolution in early pterosaurs. Because the Caturrita Formation consists of terrestrial sandstones, that evolution would have had its origins in a terrestrial, not coastal, habitat. They also concluded Faxinalipterus is the most basal known pterosaur, basal features including a lack of fusion between tibia
and fibula, a thin radius
and a coracoid that has not fused to the scapula
. However, Alexander Kellner
has suggested Faxinalipterus might be not be a pterosaur but a basal member of the Pterosauromorpha instead or, if the lack of fusion between tibia and fibula is plesiomorphic, even a sister taxon of the Ornithodira.
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 pterosaur
Pterosaur
Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period . Pterosaurs are the earliest vertebrates known to have evolved powered flight...
from the Late Triassic
Late Triassic
The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...
Caturrita Formation
Caturrita Formation
The Caturrita Formation is a rock formation found in Rio Grande do Sul, Brazil. Its sediments were deposited in the Paraná Basin. The formation has a late Carnian to early Norian age and forms part of the Santa Maria Supersequence in the upper section of the Rosário do Sul Group.-Etymology:The...
of southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
.
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...
, Faxinalipterus minima was named and described in 2010 by José Fernando Bonaparte, Marina Bento Soares and César Leandro Schultz. The generic name is derived from Faxinal do Soturno
Faxinal do Soturno
-See also:*List of municipalities in Rio Grande do Sul...
and a Latinised Greek pteron, "wing". The specific name, from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
minimus, means "smallest".
Fossils of the species have in 2002 and 2005 been found at a site 1.5 kilometres northeast of Faxinal do Sotorno, Rio Grande do Sul
Rio Grande do Sul
Rio Grande do Sul is the southernmost state in Brazil, and the state with the fifth highest Human Development Index in the country. In this state is located the southernmost city in the country, Chuí, on the border with Uruguay. In the region of Bento Gonçalves and Caxias do Sul, the largest wine...
, from the Caturrita Formation dating from the Carnian
Carnian
The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...
-Norian
Norian
The Norian is a division of the Triassic geological period. It has the rank of an age or stage . The Norian lasted from 216.5 ± 2.0 to 203.6 ± 1.5 million years ago. It was preceded by the Carnian and succeeded by the Rhaetian.-Stratigraphic definitions:The Norian was named after the Noric Alps in...
, 220 - 215 million years old. 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...
, UFRGS PV0927T, is part of the collection of the Universidade Federal do Rio Grande do Sul and consists of several, partially fragmentary, limb elements, perhaps of a single individual. These do not include bones from the hand. A upper jaw fragment, a left maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
with three teeth, has been referred to the species.
Faxinalipterus is a rather small animal, with an estimated total humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
length of eighteen millimetres. The size has been compared to that of a sparrow
Sparrow
The sparrows are a family of small passerine birds, Passeridae. They are also known as true sparrows, or Old World sparrows, names also used for a genus of the family, Passer...
. The hind limbs, much better conserved than the front limbs, are relatively long. From the maxilla it can be inferred that the skull is deep and lightly built with large openings. The maxillary teeth, probably numbering eighteen, are elongated and recurved.
The describers have assigned Faxinalipterus to the Pterosauria, based on its long hollow limbs and saddle-shaped upper joint of the relatively short and robust humerus, suitable to perform a wing stroke. They see it as perhaps the oldest pterosaur known, as it possibly predates European finds from the Norian. That the possible age difference cannot be large, they see as an indication of rapid evolution in early pterosaurs. Because the Caturrita Formation consists of terrestrial sandstones, that evolution would have had its origins in a terrestrial, not coastal, habitat. They also concluded Faxinalipterus is the most basal known pterosaur, basal features including a lack of fusion between 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 fibula, a thin radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...
and a coracoid that has not fused to the scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
. However, Alexander Kellner
Alexander Kellner
Alexander Wilhelm Armin Kellner is a Liechtensteinian/Brazilian paleontologist, a leading expert in the field of the study of pterosaurs....
has suggested Faxinalipterus might be not be a pterosaur but a basal member of the Pterosauromorpha instead or, if the lack of fusion between tibia and fibula is plesiomorphic, even a sister taxon of the Ornithodira.