Beipiaopterus
Encyclopedia
Beipiaopterus is a genus
of ctenochasmatid
pterosaur
(flying reptile) from the Lower Cretaceous Yixian Formation
(Aptian
) in the People's Republic of China
.
The genus was named in 2003 by Lü Junchang. The generic name is derived from Beipiao City in Liaoning Province and a Latinised Greek pteron, "wing". The specific epithet honours paleontologist Professor Chen Peiji.
The type and only species is based on holotype
BPM 0002, a crushed partial skeleton of a subadult individual on a slab, missing the skull. It includes four cervical, fourteen dorsal, three sacral and nine caudal vertebrae, a complete left wing and two hind limbs. Remains of the soft parts have been preserved, including partial wing membranes, a membrane attached to the tibia, a "mane" on the neck and webbing of the feet. It had a wingspan of one metre and was about fifty centimetres long if the skull had the same length as the remainder of the body: 103 millimetres for the neck, ten centimetres for the rump and 37 millimetres for the tail. In the wing finger the fourth, normally most extreme, phalanx was absent; according to Lü this was not an artefact of preservation but the normal condition of the animal, one also known from Nyctosaurus
.
In 2005 a study of the wing membrane by SEM (Scanning Electron Microscope
) was published, showing it had contained many blood vessels, which indicated a rôle in the thermoregulation
and affirmed the hypothesis that pterosaurs had been warm-blooded
Lü assigned Beipiaopterus to the Ctenochasmatidae because of the elongation of the cervical vertebrae and the general form of the humerus. This was later affirmed by an exact cladistic analysis which showed that it was a basal member of the group.
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 ctenochasmatid
Ctenochasmatidae
Ctenochasmatidae is a group of pterosaurs within the suborder Pterodactyloidea.-Classification:Listing of subfamilies and genera after Unwin 2006 unless otherwise noted.* Family Ctenochasmatidae** Elanodactylus** Gegepterus...
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...
(flying reptile) from the 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...
(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...
) in the People's Republic of 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 named in 2003 by Lü Junchang. The generic name is derived from Beipiao City in Liaoning Province and a Latinised Greek pteron, "wing". The specific epithet honours paleontologist Professor Chen Peiji.
The type and only species 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...
BPM 0002, a crushed partial skeleton of a subadult individual on a slab, missing the skull. It includes four cervical, fourteen dorsal, three sacral and nine caudal vertebrae, a complete left wing and two hind limbs. Remains of the soft parts have been preserved, including partial wing membranes, a membrane attached to the tibia, a "mane" on the neck and webbing of the feet. It had a wingspan of one metre and was about fifty centimetres long if the skull had the same length as the remainder of the body: 103 millimetres for the neck, ten centimetres for the rump and 37 millimetres for the tail. In the wing finger the fourth, normally most extreme, phalanx was absent; according to Lü this was not an artefact of preservation but the normal condition of the animal, one also known from Nyctosaurus
Nyctosaurus
Nyctosaurus is a genus of pterodactyloid pterosaur, the remains of which have been found in the Niobrara Formation of the mid-western United States, which, during the late Cretaceous Period, was covered in an extensive shallow sea. The genus Nyctosaurus has had numerous species referred to it,...
.
In 2005 a study of the wing membrane by SEM (Scanning Electron Microscope
Scanning electron microscope
A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...
) was published, showing it had contained many blood vessels, which indicated a rôle in the thermoregulation
Thermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different...
and affirmed the hypothesis that pterosaurs had been warm-blooded
Lü assigned Beipiaopterus to the Ctenochasmatidae because of the elongation of the cervical vertebrae and the general form of the humerus. This was later affirmed by an exact cladistic analysis which showed that it was a basal member of the group.