Haopterus
Encyclopedia
Haopterus was a genus
of ornithocheirid
pterodactyloid pterosaur
from the Barremian
-Aptian
-age Lower Cretaceous Yixian Formation
of Liaoning
, China
.
The genus was in 2001 named by Wang Xiaolin and Lü Junchang. The type species
is Haopterus gracilis. The genus name honours Professor Hao Yichun and combines his name with a Latinised Greek pteron, "wing". The specific name, "slender-built" in Latin
, refers to the condition of the metatarsals.
The genus is based on holotype
IVPP V11726
, a crushed fossil found in 1998 at the Sihetun-locality. The layer it was discovered in, was argon-dated
at an age of 124,6 million years. It was the first Chinese pterosaur fossil preserving the skull. It consists of the front half of a subadult
, including a skull, lower jaws, pectoral girdle, sternum
, arms, cervical
and dorsal
vertebrae, partial ischium and metatarsals.
The skull is with a length of 145 millimetres long and low, lacking a crest. The snout is pointed but rounded. The maxilla
and praemaxilla are completely fused with no visible suture. The nasopraeorbital skull opening is elongated and elliptical with a length of four centimetres, 27,6% of the total skull length. The lower jaws have a length of 128 millimetres. On the front two thirds of their length teeth are present. There are twelve pairs of teeth in both the upper and the lower jaws. The teeth are robust, sharp, pointed, and curving backwards. To the front they gradually increase in length and point more to the front. The first three pairs in the praemaxilla are very small though; the describers assumed these were replacement teeth, recently erupted.
The back of the skull and the cervical vertebrae are strongly crushed, obscuring most details. Eight dorsal vertebrae are preserved, with a total length of 52 millimetres. The sternum was fan-shaped with a prominent keel. The wings are robustly built; the ulna
is with 101 millimetres longer than the wing metacarpal which has a length of 89 millimetres. The wingspan
of the type individual was estimated at 1.35 metre (4.43 ft). In comparison the hindlimbs must have been weakly built, the metatarsal having a length of just seventeen millimetres.
The authors concluded that its slender hindfeet meant that it was forced to move quadruped
ally on land, suggesting a piscivore
lifestyle as a specialised soarer.
Haopterus was by Wang classified as a member of the Pterodactylidae, mainly because of the combination of robust teeth with the lack of a skull crest. In 2006 however, a cladistic analysis by Lü showed it was a basal member of the Ornithocheiridae
.
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 ornithocheirid
Ornithocheiridae
Ornithocheiridae is a group of pterosaurs within the suborder Pterodactyloidea. They were among the last pterosaurs to possess teeth.-Classification:Listing of genera after Unwin , except where noted.* Family Ornithocheiridae** ?Aetodactylus...
pterodactyloid 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 Barremian
Barremian
The Barremian is an age in the geologic timescale between 130.0 ± 1.5 Ma and 125.0 ± 1.0 Ma). It is a subdivision of the Early Cretaceous epoch...
-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...
-age Lower Cretaceous Yixian Formation
Yixian Formation
The Yixian Formation is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans 11 million years during the early Cretaceous period...
of Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
, China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
.
The genus was in 2001 named by Wang Xiaolin and Lü Junchang. 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...
is Haopterus gracilis. The genus name honours Professor Hao Yichun and combines his name with a Latinised Greek pteron, "wing". The specific name, "slender-built" in 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...
, refers to the condition of the metatarsals.
The genus is based on 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...
IVPP V11726
Institute of Vertebrate Paleontology and Paleoanthropology
The Institute of Vertebrate Paleontology and Paleoanthropology of China is a prominent research institution and collections repository for fossils, including many dinosaur and pterosaurand cat poo specimens...
, a crushed fossil found in 1998 at the Sihetun-locality. The layer it was discovered in, was argon-dated
Potassium-argon dating
Potassium–argon dating or K–Ar dating is a radiometric dating method used in geochronology and archeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium into argon . Potassium is a common element found in many materials, such as micas, clay minerals,...
at an age of 124,6 million years. It was the first Chinese pterosaur fossil preserving the skull. It consists of the front half of a subadult
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
, including a skull, lower jaws, pectoral girdle, sternum
Sternum
The sternum or breastbone is a long flat bony plate shaped like a capital "T" located anteriorly to the heart in the center of the thorax...
, arms, cervical
Neck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
and dorsal
Dorsum (biology)
In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...
vertebrae, partial ischium and metatarsals.
The skull is with a length of 145 millimetres long and low, lacking a crest. The snout is pointed but rounded. The 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...
and praemaxilla are completely fused with no visible suture. The nasopraeorbital skull opening is elongated and elliptical with a length of four centimetres, 27,6% of the total skull length. The lower jaws have a length of 128 millimetres. On the front two thirds of their length teeth are present. There are twelve pairs of teeth in both the upper and the lower jaws. The teeth are robust, sharp, pointed, and curving backwards. To the front they gradually increase in length and point more to the front. The first three pairs in the praemaxilla are very small though; the describers assumed these were replacement teeth, recently erupted.
The back of the skull and the cervical vertebrae are strongly crushed, obscuring most details. Eight dorsal vertebrae are preserved, with a total length of 52 millimetres. The sternum was fan-shaped with a prominent keel. The wings are robustly built; the ulna
Ulna
The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...
is with 101 millimetres longer than the wing metacarpal which has a length of 89 millimetres. The wingspan
Wingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...
of the type individual was estimated at 1.35 metre (4.43 ft). In comparison the hindlimbs must have been weakly built, the metatarsal having a length of just seventeen millimetres.
The authors concluded that its slender hindfeet meant that it was forced to move quadruped
Quadruped
Quadrupedalism is a form of land animal locomotion using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet"...
ally on land, suggesting a piscivore
Piscivore
A piscivore is a carnivorous animal which eats primarily fish. Piscivory was the diet of early tetrapods , insectivory came next, then in time reptiles added herbivory....
lifestyle as a specialised soarer.
Haopterus was by Wang classified as a member of the Pterodactylidae, mainly because of the combination of robust teeth with the lack of a skull crest. In 2006 however, a cladistic analysis by Lü showed it was a basal member of the Ornithocheiridae
Ornithocheiridae
Ornithocheiridae is a group of pterosaurs within the suborder Pterodactyloidea. They were among the last pterosaurs to possess teeth.-Classification:Listing of genera after Unwin , except where noted.* Family Ornithocheiridae** ?Aetodactylus...
.
External links
- Haopterus in The Pterosauria