Dorygnathus
Encyclopedia
Dorygnathus was a genus
of pterosaur
that lived in Europe during the Early Jurassic
period, 180 million years ago when shallow seas flooded much of the continent. It had a short 1.5 meter (five feet) wingspan
, and a relatively small triangular sternum
, which is where its flight muscles attached. Its skull was long and its eye sockets were the largest opening therein. Large curved fangs that "intermeshed" when the jaws closed featured prominently at the front of the snout while smaller, straighter teeth lined the back. Having variable teeth, a condition called heterodont
y, is rare in modern reptiles but more common in primitive pterosaurs. The heterodont dentition in Dorygnathus is consistent with a piscivorous
(fish-eating) diet. The fifth digit on the hindlimbs of Dorygnathus was unusually long and oriented to the side. Its function is not certain, but the toe may have supported a membrane like those supported by its wing-fingers and pteroids. Dorygnathus was according to David Unwin related to the Late Jurassic
pterosaur, Rhamphorhynchus and was a contemporary of Campylognathoides
in Holzmaden and Ohmden.
dating from the Toarcian
, were discovered near Banz
, Bavaria
and in 1830 described by Carl Theodori as Ornithocephalus banthensis, the specific name referring to Banz. The holotype
, a lower jaw, is PSB 757. The fossils were studied by Christian Erich Hermann von Meyer
in 1831 and again by Theodori in 1852 when he referred them to the genus Rhamphorhynchus. In this period a close affinity was assumed with a pterosaur known from Britain, later named Dimorphodon
. Some fossils were sent to a professor of paleontology in Munich
named Johann Andreas Wagner
. It was he who, having studied new finds by Alfred Oppel in 1856 and 1858, after Richard Owen
had named Dimorphodon concluded that the German type was clearly different and that therefore a new genus of pterosaur should be erected, which he formally named Dorygnathus in 1860, from Greek dory
, "spear" and gnathos, "jaw". Much more complete remains have been found since in other German locales and especially in Württemberg
, including Holzmaden
, Ohmden
, and Zell
. One specimen, SMNS 81840, has in 1978 been dug up in Nancy, France
. Dorygnathus fossils were often found in the spoil heaps where unusable rock was dumped from slate
quarries worked by local farmers. Most fossils were found in two major waves, one during the twenties, the other during the eighties of the twentieth century. Since then the rate of discovery has slowed considerably because the demand for slate has strongly diminished and many small quarries have closed. At present over fifty specimens have been collected, many of them are preserved in the collection of the State Museum of Natural History Stuttgart
, as by law paleontological finds in Baden-Württemberg
are property of this Bundesland
. Due to the excellent preserval of the later found fossils, Dorygnathus has generated much interest by pterosaur researchers, important studies having been dedicated to the species by Felix Plieninger, Gustav von Arthaber, and more recently Kevin Padian
.
Dorygnathus in general has the build of a basal, i.e. non-pterodactyloid
pterosaur: a short neck, a long tail and short metacarpals — although for a basal pterosaur the neck and metacarpals of Dorygnathus are again relatively long. The skull is elongated and pointed. The largest known cranium, that of specimen MBR 1920.16 prepared by Bernard Hauff in 1915 and eventually acquired by the Humboldt Museum
in Berlin
, has a length of sixteen centimetres. In the skull the eye socket forms the largest opening, larger than the fenestra antorbitalis that is clearly separated from the slit-like bony naris. No bony crest is visible on the rather straight top of the skull or snout. The lower jaws are thin at the back but deeper toward the front where they fuse into the symphysis
ending in a toothless point after which the genus has been named. In MBR 1920.16, the mandibula as a whole has a length of 147 millimetres.
In the lower jaws the first three pairs of teeth are very long, sharp and pointing outwards and forwards. They contrast with a row of eight or more upright-standing much smaller teeth that gradually diminish in size towards the back of the lower jaw. No such extreme contrast exists in the upper jaws, but the four teeth in the premaxilla
are longer than the seven in the maxilla
that again become smaller posteriorly. The total number of teeth is thus at least 44. The long upper and lower front teeth interlaced when the beak was closed; due to their extreme length they then projected considerably beyond the upper and lower margins of the head.
According to Padian, eight cervical, fourteen dorsal, three or four sacral and twenty-seven or twenty-eight caudal vertebrae are present. The exceptional fourth sacral is the first of the normal caudal series. The number of caudals is not certain because their limits are obscured by long thread-like extensions, stiffening the tail. The cervical vertebrae are rather long and strongly built, their upper surface having a roughly square cross-section. They carry double-headed thin cervical ribs. The dorsal vertebrae are more rounded with flat spines; the first three or four carry ribs that contact the sternal ribs; the more posterior ribs contact the gastralia. The first five or six, rather short, caudal vertebrae form a flexible tail base. To the back the caudals grow longer and are immobilised by their intertwining extensions with a length of up to five vertebrae which together surround the caudals with a bony network, allowing the tail to function as a rudder.
The breastbone is triangular and relatively small; Padian has suggested it may have been extended at its back with a cartilaginous tissue. It is connected to the coracoid which in older individuals is fused to the longer scapula
forming a saddle-shaped shoulder joint. The humerus
has a triangular deltopectoral crest and is pneumatised. The lower arm is 60% longer than the upper arm. From the five carpal bones in the wrist a short but robust pteroid points towards the neck, in the living animal a support for a flight membrane, the propatagium. The first three metacarpals are connected to three small fingers, equipped with short but strongly curved claws; the fourth to the wing finger, in which the second or third phalanx
is the longest; the first or fourth the shortest. The wing finger supports the main flight membrane.
In the pelvis
, the ilium
, ischium and pubis
are fused. The ilium is elongated with a length of six vertebrae. The lower leg, in which the lower two thirds of the tibia
and fibula of adult specimens are fused, is a third shorter than the thighbone, the head of which makes an angle of 45° with its shaft. The proximal tarsals
are never fused in a separate astragalocalcaneum; a tibiotarsus
is formed. The third metatarsal is the longest; the fifth is connected to a toe of which the second phalanx shows a 45° bend and has a blunt and broad end; it perhaps supported a membrane between the legs, a cruropatagium.
In some specimens, soft parts have been preserved but these are rare and limited, providing little information. It is unknown whether the tail featured a vane on its end, as with Rhamphorhynchus. However, Ferdinand Broili reported the presence of hairs in specimen BSP 1938 I 49, an indication that Dorygnathus also had fur and an elevated metabolism
, as is presently assumed for all pterosaurs.
, to which the specific name refers, by teacher H. Herppich, who donated it to the private collection of Günther Eicken, a local amateur paleontologist at Bayreuth, where it still resides. As a result the exemplar has no official inventory number. The fossil comprises a shoulder-blade with wing, a partial leg, a rib and a caudal vertebra. Wild justified the creation of a new species name by referring to the great size, with an about 50% larger wingspan than with a typical specimen; the short lower leg and the long wing.
Padian in 2008 pointed out that D. banthensis specimen MBR 1977.21, the largest then known, has with a wingspan of 169 centimetres an even larger size; that wing and lower leg proportions are rather variable in D. banthensis and that the geological age is comparable. He concluded that D. mistelgauensis is a subjective junior synonym of D. banthensis.
in 1978. Modern exact cladistic
analyses of the relationships of Dorygnathus have not resulted in a consensus. David Unwin in 2003 found that it belonged to the clade
Rhamphorhynchinae, but analyses by Alexander Kellner
resulted in a much more basal position, below Dimorphodon or Peteinosaurus
. Padian, using a comparative method, in 2008 concluded that Dorygnathus was close to Scaphognathus and Rhamphorhynchus in the phylogenetic tree
but also that these species were forming a series of successive off-shoots, meaning that they would not be united in a separate clade. This was again contradicted by the results of a cladistic study by Brian Andres in 2010 showing that Dorygnathus was part of a monophyletic Rhamphorhynchinae. The following cladogram shows the position of Dorygnathus according to Andres:
that however is much more rare. Very young juveniles of Dorygnathus are unknown, the smallest discovered specimen having a wingspan of sixty centimetres; perhaps they were unable to venture far over open sea. Padian concluded that Dorygnathus after a relatively fast growth in its early years, faster than any modern reptile of the same size, kept slowly growing after having reached sexual maturity, which would have resulted in exceptionally large individuals with a 1.7 metres wingspan.
On land, Dorygnathus was probably not a good climber; its claws show no special adaptations for this type of locomotion. According to Padian, Dorygnathus, as a small pterosaur with a long tail, was well capable of bipedal movement, though its long metacarpals would make him better suited for a quadrupedal walk than most basal pterosaurs. Most researchers however, today assume quadrupedality for all pterosaurs.
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...
that lived in Europe during the Early 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...
period, 180 million years ago when shallow seas flooded much of the continent. It had a short 1.5 meter (five feet) 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...
, and a relatively small triangular 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...
, which is where its flight muscles attached. Its skull was long and its eye sockets were the largest opening therein. Large curved fangs that "intermeshed" when the jaws closed featured prominently at the front of the snout while smaller, straighter teeth lined the back. Having variable teeth, a condition called heterodont
Heterodont
The anatomical term heterodont refers to animals which possess more than a single tooth morphology. For example, members of the Synapsida generally possess incisors, canines , premolars, and molars. The presence of heterodont dentition is evidence of some degree of feeding/hunting specialization...
y, is rare in modern reptiles but more common in primitive pterosaurs. The heterodont dentition in Dorygnathus is consistent with a piscivorous
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....
(fish-eating) diet. The fifth digit on the hindlimbs of Dorygnathus was unusually long and oriented to the side. Its function is not certain, but the toe may have supported a membrane like those supported by its wing-fingers and pteroids. Dorygnathus was according to David Unwin related to the Late Jurassic
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...
pterosaur, Rhamphorhynchus and was a contemporary of Campylognathoides
Campylognathoides
Campylognathoides was a genus of "rhamphorhynchoid" pterosaur, discovered in the Württemberg Lias deposits, the first specimen consisting of wing fragments...
in Holzmaden and Ohmden.
Discovery
The first remains of Dorygnathus, isolated bones and jaw fragments from the Schwarzjura, the Posidonia ShalePosidonia Shale
The Posidonia Shale is a Lower Jurassic geological formation famous for its exceptionally well-preserved complete skeletons of fossil marine fish and reptiles. The Posidonienschiefer as German paleontologists call it, takes its name from the ubiquitous fossils of Posidonia bronni that characterize...
dating from the Toarcian
Toarcian
The Toarcian is, in the ICS' geologic timescale, an age or stage in the Early or Lower Jurassic. It spans the time between 183.0 Ma and 175.6 Ma...
, were discovered near Banz
Banz Abbey
Banz Abbey , now known as Banz Castle , is a former Benedictine monastery, since 1978 a part of the town of Bad Staffelstein north of Bamberg, Bavaria, southern Germany.-History:...
, Bavaria
Bavaria
Bavaria, formally the Free State of Bavaria is a state of Germany, located in the southeast of Germany. With an area of , it is the largest state by area, forming almost 20% of the total land area of Germany...
and in 1830 described by Carl Theodori as Ornithocephalus banthensis, the specific name referring to Banz. 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...
, a lower jaw, is PSB 757. The fossils were studied by Christian Erich Hermann von Meyer
Christian Erich Hermann von Meyer
Christian Erich Hermann von Meyer was a German palaeontologist.He was born at Frankfurt am Main.In 1832 von Meyer issued a work entitled Palaeologica, and in course of time he published a series of memoirs on various fossil organic remains: molluscs, crustaceans, fishes and higher vertebrata,...
in 1831 and again by Theodori in 1852 when he referred them to the genus Rhamphorhynchus. In this period a close affinity was assumed with a pterosaur known from Britain, later named Dimorphodon
Dimorphodon
Dimorphodon was a genus of medium-sized pterosaur from the early Jurassic Period. It was named by paleontologist Richard Owen in 1859. Dimorphodon means "two-form tooth", derived from Greek δι/di meaning 'two', μορφη/morphe meaning 'shape' and οδων/odon meaning 'tooth', referring to the fact that...
. Some fossils were sent to a professor of paleontology in Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
named Johann Andreas Wagner
Johann Andreas Wagner
Johann Andreas Wagner was a German palaeontologist, zoologist and archaeologist.Wagner was a professor at the University of Munich, and curator of the Zoologische Staatssammlung ....
. It was he who, having studied new finds by Alfred Oppel in 1856 and 1858, after Richard Owen
Richard Owen
Sir Richard Owen, FRS KCB was an English biologist, comparative anatomist and palaeontologist.Owen is probably best remembered today for coining the word Dinosauria and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection...
had named Dimorphodon concluded that the German type was clearly different and that therefore a new genus of pterosaur should be erected, which he formally named Dorygnathus in 1860, from Greek dory
Dory (spear)
The dory or doru - ie not pronounced like the fish - is a spear that was the chief armament of hoplites in Ancient Greece. The word "dory" is first attested in Homer with the meanings of "wood" and "spear". Homeric heroes hold two dorys...
, "spear" and gnathos, "jaw". Much more complete remains have been found since in other German locales and especially in Württemberg
Württemberg
Württemberg , formerly known as Wirtemberg or Wurtemberg, is an area and a former state in southwestern Germany, including parts of the regions Swabia and Franconia....
, including Holzmaden
Holzmaden
Holzmaden is a town in Baden-Württemberg, Germany that lies between Stuttgart and Ulm.The ground in and around the city contains rich layers of well preserved fossils of the Jurassic period. The fossils are found in the 160 million year old Posidonia Shale and displayed in the local Museum Hauff...
, Ohmden
Ohmden
Ohmden is a town in the district of Esslingen in Baden-Württemberg in Germany....
, and Zell
Zell
-Austria:*Zell am See, in Salzburg state*Zell am Ziller, in Tyrol*Zell, Carinthia, in Carinthia*in Upper Austria:**Bad Zell**Zell am Moos**Zell an der Pram**Zell am Pettenfirst-Germany:...
. One specimen, SMNS 81840, has in 1978 been dug up in Nancy, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
. Dorygnathus fossils were often found in the spoil heaps where unusable rock was dumped from slate
Slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. The result is a foliated rock in which the foliation may not correspond to the original sedimentary layering...
quarries worked by local farmers. Most fossils were found in two major waves, one during the twenties, the other during the eighties of the twentieth century. Since then the rate of discovery has slowed considerably because the demand for slate has strongly diminished and many small quarries have closed. At present over fifty specimens have been collected, many of them are preserved in the collection of the State Museum of Natural History Stuttgart
State Museum of Natural History Stuttgart
The State Museum of Natural History Stuttgart is one of the two state of Baden-Württemberg's natural history museums...
, as by law paleontological finds in Baden-Württemberg
Baden-Württemberg
Baden-Württemberg is one of the 16 states of Germany. Baden-Württemberg is in the southwestern part of the country to the east of the Upper Rhine, and is the third largest in both area and population of Germany's sixteen states, with an area of and 10.7 million inhabitants...
are property of this Bundesland
States of Germany
Germany is made up of sixteen which are partly sovereign constituent states of the Federal Republic of Germany. Land literally translates as "country", and constitutionally speaking, they are constituent countries...
. Due to the excellent preserval of the later found fossils, Dorygnathus has generated much interest by pterosaur researchers, important studies having been dedicated to the species by Felix Plieninger, Gustav von Arthaber, and more recently Kevin Padian
Kevin Padian
Kevin Padian is a Professor of Integrative Biology at the University of California, Berkeley, Curator of Paleontology, University of California Museum of Paleontology and President of the National Center for Science Education. Padian's area of interest is in vertebrate evolution, especially the...
.
Description
Pterodactyloidea
Pterodactyloidea forms one of the two suborders of pterosaurs , and contains the most derived members of this group of flying reptiles...
pterosaur: a short neck, a long tail and short metacarpals — although for a basal pterosaur the neck and metacarpals of Dorygnathus are again relatively long. The skull is elongated and pointed. The largest known cranium, that of specimen MBR 1920.16 prepared by Bernard Hauff in 1915 and eventually acquired by the Humboldt Museum
Humboldt Museum
The Museum für Naturkunde, officially the ' or Naturkundemuseum , occasionally known as the Humboldt Museum, is a natural history museum in Berlin, Germany. Usually the museum's name is abbreviated MFN...
in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
, has a length of sixteen centimetres. In the skull the eye socket forms the largest opening, larger than the fenestra antorbitalis that is clearly separated from the slit-like bony naris. No bony crest is visible on the rather straight top of the skull or snout. The lower jaws are thin at the back but deeper toward the front where they fuse into the symphysis
Symphysis
A symphysis is a fibrocartilaginous fusion between two bones. It is a type of cartilaginous joint, specifically a secondary cartilaginous joint.1.A symphysis is an amphiarthrosis, a slightly movable joint.2.A growing together of parts or structures...
ending in a toothless point after which the genus has been named. In MBR 1920.16, the mandibula as a whole has a length of 147 millimetres.
In the lower jaws the first three pairs of teeth are very long, sharp and pointing outwards and forwards. They contrast with a row of eight or more upright-standing much smaller teeth that gradually diminish in size towards the back of the lower jaw. No such extreme contrast exists in the upper jaws, but the four teeth in the premaxilla
Premaxilla
The incisive bone is the portion of the maxilla adjacent to the incisors. It is a pair of small cranial bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals....
are longer than the seven in 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...
that again become smaller posteriorly. The total number of teeth is thus at least 44. The long upper and lower front teeth interlaced when the beak was closed; due to their extreme length they then projected considerably beyond the upper and lower margins of the head.
According to Padian, eight cervical, fourteen dorsal, three or four sacral and twenty-seven or twenty-eight caudal vertebrae are present. The exceptional fourth sacral is the first of the normal caudal series. The number of caudals is not certain because their limits are obscured by long thread-like extensions, stiffening the tail. The cervical vertebrae are rather long and strongly built, their upper surface having a roughly square cross-section. They carry double-headed thin cervical ribs. The dorsal vertebrae are more rounded with flat spines; the first three or four carry ribs that contact the sternal ribs; the more posterior ribs contact the gastralia. The first five or six, rather short, caudal vertebrae form a flexible tail base. To the back the caudals grow longer and are immobilised by their intertwining extensions with a length of up to five vertebrae which together surround the caudals with a bony network, allowing the tail to function as a rudder.
The breastbone is triangular and relatively small; Padian has suggested it may have been extended at its back with a cartilaginous tissue. It is connected to the coracoid which in older individuals is fused to the longer scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
forming a saddle-shaped shoulder joint. The humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
has a triangular deltopectoral crest and is pneumatised. The lower arm is 60% longer than the upper arm. From the five carpal bones in the wrist a short but robust pteroid points towards the neck, in the living animal a support for a flight membrane, the propatagium. The first three metacarpals are connected to three small fingers, equipped with short but strongly curved claws; the fourth to the wing finger, in which the second or third phalanx
Phalanx bones
In anatomy, phalanx bones are those that form the fingers and toes. In primates such as humans and monkeys, the thumb and big toe have two phalanges, while the other fingers and toes consist of three. Phalanges are classified as long bones.The phalanges do not have individual names...
is the longest; the first or fourth the shortest. The wing finger supports the main flight membrane.
In the pelvis
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
, the ilium
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...
, ischium and pubis
Pubis (bone)
In vertebrates, the pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....
are fused. The ilium is elongated with a length of six vertebrae. The lower leg, in which the lower two thirds of the 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 of adult specimens are fused, is a third shorter than the thighbone, the head of which makes an angle of 45° with its shaft. The proximal tarsals
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...
are never fused in a separate astragalocalcaneum; a tibiotarsus
Tibiotarsus
The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia.A similar structure also occurred in the Mesozoic Heterodontosauridae...
is formed. The third metatarsal is the longest; the fifth is connected to a toe of which the second phalanx shows a 45° bend and has a blunt and broad end; it perhaps supported a membrane between the legs, a cruropatagium.
In some specimens, soft parts have been preserved but these are rare and limited, providing little information. It is unknown whether the tail featured a vane on its end, as with Rhamphorhynchus. However, Ferdinand Broili reported the presence of hairs in specimen BSP 1938 I 49, an indication that Dorygnathus also had fur and an elevated metabolism
Metabolism
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...
, as is presently assumed for all pterosaurs.
Dorygnathus mistelgauensis
In 1971 Rupert Wild described and named a second species: Dorygnathus mistelgauensis, based on a specimen collected in a brick pit near the railway station of MistelgauMistelgau
Mistelgau is a municipality in the district of Bayreuth in Bavaria in Germany....
, to which the specific name refers, by teacher H. Herppich, who donated it to the private collection of Günther Eicken, a local amateur paleontologist at Bayreuth, where it still resides. As a result the exemplar has no official inventory number. The fossil comprises a shoulder-blade with wing, a partial leg, a rib and a caudal vertebra. Wild justified the creation of a new species name by referring to the great size, with an about 50% larger wingspan than with a typical specimen; the short lower leg and the long wing.
Padian in 2008 pointed out that D. banthensis specimen MBR 1977.21, the largest then known, has with a wingspan of 169 centimetres an even larger size; that wing and lower leg proportions are rather variable in D. banthensis and that the geological age is comparable. He concluded that D. mistelgauensis is a subjective junior synonym of D. banthensis.
Phylogeny
The affinity between Dorygnathus and Dimorphodon, assumed by early researchers, was largely based on a superficial resemblance in tooth form. Baron Franz Nopcsa in 1928 assigned the species to the Rhamphorhynchinae, which was confirmed by Peter WellnhoferPeter Wellnhofer
Peter Wellnhofer is a German paleontologist at the "Bayerische Staatssammlung fur Paläontologie" in Munich. He is best known for his work on the various fossil specimens of Archaeopteryx or "Urvogel", the first known bird...
in 1978. Modern exact cladistic
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...
analyses of the relationships of Dorygnathus have not resulted in a consensus. David Unwin in 2003 found that it belonged to the clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
Rhamphorhynchinae, but analyses by Alexander Kellner
Alexander Kellner
Alexander Wilhelm Armin Kellner is a Liechtensteinian/Brazilian paleontologist, a leading expert in the field of the study of pterosaurs....
resulted in a much more basal position, below Dimorphodon or Peteinosaurus
Peteinosaurus
Peteinosaurus was a prehistoric reptile genus belonging to the Pterosauria. It lived in the late Triassic period in the middle Norian .-Name:...
. Padian, using a comparative method, in 2008 concluded that Dorygnathus was close to Scaphognathus and Rhamphorhynchus in the phylogenetic tree
Phylogenetic tree
A phylogenetic tree or evolutionary tree is a branching diagram or "tree" showing the inferred evolutionary relationships among various biological species or other entities based upon similarities and differences in their physical and/or genetic characteristics...
but also that these species were forming a series of successive off-shoots, meaning that they would not be united in a separate clade. This was again contradicted by the results of a cladistic study by Brian Andres in 2010 showing that Dorygnathus was part of a monophyletic Rhamphorhynchinae. The following cladogram shows the position of Dorygnathus according to Andres:
Paleobiology
Dorygnathus is commonly thought to have had a piscivorous way of living, catching fish or other slippery sea-creatures with its long teeth. This is confirmed by the fact that the fossils have been found in marine sediments, deposited in the seas of the European Archipelago. In these it is present together with the pterosaur CampylognathoidesCampylognathoides
Campylognathoides was a genus of "rhamphorhynchoid" pterosaur, discovered in the Württemberg Lias deposits, the first specimen consisting of wing fragments...
that however is much more rare. Very young juveniles of Dorygnathus are unknown, the smallest discovered specimen having a wingspan of sixty centimetres; perhaps they were unable to venture far over open sea. Padian concluded that Dorygnathus after a relatively fast growth in its early years, faster than any modern reptile of the same size, kept slowly growing after having reached sexual maturity, which would have resulted in exceptionally large individuals with a 1.7 metres wingspan.
On land, Dorygnathus was probably not a good climber; its claws show no special adaptations for this type of locomotion. According to Padian, Dorygnathus, as a small pterosaur with a long tail, was well capable of bipedal movement, though its long metacarpals would make him better suited for a quadrupedal walk than most basal pterosaurs. Most researchers however, today assume quadrupedality for all pterosaurs.
See also
- CampylognathoidesCampylognathoidesCampylognathoides was a genus of "rhamphorhynchoid" pterosaur, discovered in the Württemberg Lias deposits, the first specimen consisting of wing fragments...
- HolzmadenHolzmadenHolzmaden is a town in Baden-Württemberg, Germany that lies between Stuttgart and Ulm.The ground in and around the city contains rich layers of well preserved fossils of the Jurassic period. The fossils are found in the 160 million year old Posidonia Shale and displayed in the local Museum Hauff...
- List of pterosaurs
- Rhamphorhynchus