Campylognathoides
Encyclopedia
Campylognathoides was a genus
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 "rhamphorhynchoid" 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...

, discovered in the 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....

 Lias
Lias
Lias may refer to:*In geology:**The Lias Group, a group in the stratigraphy of Great Britain, formed during the Late Triassic to Early Jurassic epochs. It includes the Blue Lias and White Lias...

 deposits, the first specimen consisting of wing fragments. Further better preserved specimens were found in the Holzmaden shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...

 and it was based on these specimens that Felix Plieninger erected a new genus.

Discovery

In 1858 Friedrich August Quenstedt named a new species of Pterodactylus
Pterodactylus
Pterodactylus is a genus of pterosaurs, whose members are popularly known as pterodactyls. It was the first to be named and identified as a flying reptile...

: P. liasicus. It was based on a fossil, 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...

 GPIT 9533, consisting of some wing bones, found on the Wittberg near Metzingen
Metzingen
Metzingen is a Swabian city with about 22,000 inhabitants, in the state of Baden-Württemberg in the southwest of Germany, south of Stuttgart.-History:The city is mentioned for the first time in documents from 1075...

 in layers dating from the early 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...

, about 180 million years old. The specific name referred to the Lias
Lias
Lias may refer to:*In geology:**The Lias Group, a group in the stratigraphy of Great Britain, formed during the Late Triassic to Early Jurassic epochs. It includes the Blue Lias and White Lias...

. Quenstedt thought he had identified long metacarpals in the wing, concluding that the new species was therefore not belonging to more basal genera, like the long-tailed Rhamphorhynchus.

In 1893 commercial fossil collector Bernhard Hauff sr. discovered a skeleton of a large pterosaur near 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...

. In 1894 Felix Plieninger based a new genus on this specimen: Campylognathus. The genus name is derived from Greek kampylos, "bent", and gnathos, "jaw", in reference to the bent lower jaw. 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 Campylognathus zitteli. The specific name honours Alfred von Zittel. The holotype is SMNS 9787.

In 1897 Hauff prepared another specimen that eventually in 1903 was acquired by the Carnegie Museum of Natural History
Carnegie Museum of Natural History
Carnegie Museum of Natural History, located at 4400 Forbes Avenue in the Oakland neighborhood of Pittsburgh, Pennsylvania, USA, was founded by the Pittsburgh-based industrialist Andrew Carnegie in 1896...

 at Pittsburgh. This fossil, CM 11424, is due to its completeness the best source of information about the genus.

In 1901 Plieninger for the first time studied P. liasicus and discovered that Quenstedt had mistaken the, in reality short, metacarpal, for a coracoid, meaning it was a basal pterosaur. In 1906 Plieninger referred P. liasicus and the Pittsburgh specimen to Campylognathus, though not yet establishing the specific status of each of the three exemplars. In 1907 however, Plieninger recognised a second species of Campylognathus: C. liasicus, to which CM 11424 was referred also.

Norwegian entomologist Embrik Strand
Embrik Strand
Embrik Strand was an arachnologist who classified many insect and spider species, including the greenbottle blue tarantula....

 discovered in the 1920s that the name Campylognathus been previously been used for the African bug Campylognathus nigrensis, a genus of the Heteroptera
Heteroptera
Heteroptera is a group of about 40,000 species of insects in the Hemiptera. Sometimes called "true bugs", that name more commonly refers to Hemiptera as a whole, and "typical bugs" might be used as a more unequivocal alternative since among the Hemiptera the heteropterans are most consistently and...

 named in 1890. As the name was thus preoccupied, he renamed the pterosaur Campylognathoides in 1928.

During the twentieth century new finds have brought the number of known specimens to about a dozen.

Anatomy and gait

Compared to its contemporary from the same layers Dorygnathus
Dorygnathus
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 wingspan, and a relatively small triangular sternum, which is where its flight muscles attached. Its skull...

, the snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...

 on this genus is relatively short, though the skull is still in general elongated, be it much lighter built. The large eye sockets, placed low in the skull above a narrow jugal
Jugal
The jugal is a skull bone found in most reptiles, amphibians, and birds. In mammals, the jugal is often called the malar or Zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by species....

, have caused some researchers to speculate that Campylognathoides had especially acute vision, or possibly even a nocturnal lifestyle. The back of the skull is relatively high and flat, with a sudden downturn just in front of the eyes. The snout ends in a slender point curving a bit upwards at its very end. A large part of the snout is occupied by long bony nares. Below them a small triangular skull opening, the fenestra antorbitalis is present.

Reflecting the more shallow snout, the teeth of Campylognathoides are also short and not at all laniaries or fang-like as in the markedly 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...

 Dorygnathus. They are conical and recurved but have a broad base with the point bevelled off from the inside forming a sharp and strong cutting surface. In the upper jaw there are four rather widely spaced teeth in the praemaxilla gradually increasing in size from the front to the back; the fourth pair of teeth is the largest. Behind them are ten smaller teeth 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...

, gradually decreasing posteriorely. In the lower jaw there are twelve to fourteen teeth present in C. liasicus, sixteen to nineteen in C. zitteli. The largest total number is thus 66.

According to a study by 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...

 there are eight cervical vertebrae, fourteen dorsals, four or five sacrals and up to 38 caudal vertebrae. The tail base is flexible with about six short vertebrae; behind them the caudals elongate and are stiffened by very long extensions allowing the tail to function as a rudder.

The 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...

 of Campylognathoides was a rather large rectangular plate of bone with a short forward-facing crest called a cristospina. The upper arm is short but robust with a square deltopectoral crest. The lower arm too is short but wing length is considerable due to the hand, which has short metacarpals but a very long wing finger for a basal pterosaur, of which the second phalanx is the largest. The pteroid is short and robust.

The pelvis is not very well known. A fossil collector found a well preserved Campylognathoides hip in a Braunschweig shale quarry in 1986
1986 in paleontology
-Newly named dinosaurs:Data courtesy of George Olshevsky's dinosaur genera list and Dr. Jeremy Montague's dinosaur genus database.-New taxa:-Pterosaurs:...

. This pelvis, BSP 1985 I 87, proved to be scientifically significant because the hip socket was according to Peter Wellnhofer
Peter 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 an upward lateral position, preventing the animal from being able to orient its legs erectly like in dinosaurs, birds and mammals. This would prove that Campylognathoides was not well able to walk on its hind legs but must have walked 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. This gait posture has been confirmed in other "rhamphorhynchoids" (i.e. basal pterosaurs) as well. However, Padian in 2009 concluded the opposite, stating that an erected position was necessary to place the feet on the ground and that, though a quadrupedal gait was possible, a bipedal way of locomotion was a precondition for a fast gait. This subject remains highly controversial.

The leg is rather short and the feet are small. The fifth toe, often interpreted as carrying a membrane between the legs, is exceptionally short for a basal pterosaur.

Species

Three species of Campylognathoides have been named:
  • Campylognathoides zitteli (Plieninger, 1894) is 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...

    .
The larger Holzmaden Campylognathoides, C. zitteli, had a six foot (1.825 metres for SMNS 9787) wingspan.
  • Campylognathoides liasicus (Quenstedt, 1858 [originally Pterodactylus
    Pterodactylus
    Pterodactylus is a genus of pterosaurs, whose members are popularly known as pterodactyls. It was the first to be named and identified as a flying reptile...

     liasicus
    ])
C. liasicus had a three foot wingspan, making it smaller than its Holzmaden contemporary, C. zitteli.
  • "Campylognathoides" indicus (Jain, 1974
    1974 in paleontology
    -Newly named dinosaurs:Data courtesy of George Olshevsky's dinosaur genera list and Dr. Jeremy Montague's dinosaur genus database.-New taxa:-Non-mammalian:-References:...

    )
C. indicus was described by Sohan Lal Jain
Sohan Lal Jain
Sohan Lal Jain is an Indian paleontologist, who worked for many years at the Indian Statistical Institute, Kolkata. The large herbivorous sauropod dinosaur genus Jainosaurus, was named in his honour after it was identified as a distinct genus. It was earlier thought to be a species of...

 on the basis of a fragment of jaw, ISI R. 48, recovered from Chanda district, India. 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...

 considers this a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...

, possibly based on a fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 fossil. That the Kota Formation
Kota Formation
The Kota Formation is a geological formation in India. It dates back to the Hettangian-Pliensbachian.-Vertebrate paleofauna:Indeterminate thyreophoran remains geographically present in Andhra Pradesh State, India.-Invertebrate paleofauna:...

 in which it was found, has since been redated to the Middle Jurassic
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....

 or later, seems to preclude any close connection to Campylognathoides, even if it were a pterosaur.


The distinction between C. liasicus and C. zitteli is problematical. Plieninger merely recognised the smaller species because he considered its fossil too poor in quality to refer other specimens to. However, in 1925 Swedish researcher Carl Wiman
Carl Wiman
Carl Wiman was a Swedish paleontologist and the first professor of paleontology at Uppsala University. He published on a variety of topics, including extinct penguins, and dinosaur fossils sent to Sweden from China and the San Juan Basin of New Mexico...

, studying specimen UUPM R157, concluded that a fundamental morphological difference could distinguish the two species: C. zitteli has a proportionally much longer wing. In 2008 however, Padian pointed out that this might well have been a matter of ontogenetic development, larger individuals growing extra large wings to limit the wing load. Other differences, such as the larger number of teeth in the lower jaw, a longer snout and nares, five instead of four sacrals, perpendicular sacral ribs and a longer leg, might conceivably also be size-related. Final proof could only be given by a continuous growth series, as previously has been done in the case of Rhamphorhynchus and Pterodactylus. Provisionally Padian kept distinguishing two species, but moved two specimens to C. zitteli: SMNS 51100 and GPIT 24470, because of their larger size and morphological similarities.

Phylogeny

Plieninger in his later publications assigned Campylognathus to the "Rhamphorhynchoidea
Rhamphorhynchoidea
The Rhamphorhynchoidea forms one of the two suborders of pterosaurs and represent an evolutionary grade of primitive members of this group of flying reptiles. This suborder is paraphyletic in relation to the Pterodactyloidea, which arose from within the Rhamphorhynchoidea, not from a more distant...

". As this suborder is a paraphyletic assemblage of not specially related basal pterosaurs, this classification merely states the negative fact that it was not a pterodactyloid. A positive determination was first attempted by Baron Franz Nopcsa who in 1928 assigned the genus to the subfamily Rhamphorhynchinae within the family Rhamphorhynchidae
Rhamphorhynchidae
Rhamphorhynchidae is a group of early "rhamphorhynchoid" pterosaurs named after Rhamphorhynchus, that lived in the Late Jurassic. The family Rhamphorhynchidae was named in 1870 by Harry Govier Seeley.-Classification:...

. After a period in which very little work was done on pterosaur systematics, in 1967 Oskar Kuhn
Oskar Kuhn
Oskar Kuhn was a German palaeontologist.-Life and career:Kuhn was educated in Dinkelsbühl and Bamberg and then studied natural science, specialising in geology and paleontology, at the University of Munich, from which he received his D. Phil...

 placed Campylognathoides in its own subfamily within the Rhamphorhynchidae, the Campylognathoidinae. However, in 1974 Peter Wellnhofer
Peter 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...

 concluded that it was placed in a more basal position 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...

, below the Rhamphorhynchidae. In the early twenty-first century this was confirmed by the first extensive exact cladistic analyses. In 2003 both David Unwin and Alexander Kellner
Alexander Kellner
Alexander Wilhelm Armin Kellner is a Liechtensteinian/Brazilian paleontologist, a leading expert in the field of the study of pterosaurs....

 introduced a 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...

 Campylognathoididae
Campylognathoididae
Campylognathoididae is a group of early "rhamphorhynchoid" pterosaurs named after Campylognathoides, that lived in the Late Jurassic. The family Campylognathoididae was named in 1967 by Oskar Kuhn, originally as the subfamily Campylognathoidinae....

; within Unwin's terminology this clade is the sister clade of the Breviquartossa within the Lonchognatha; applying Kellner's terminology it is the most basal off-shoot within the Novialoidea. There is no material difference between the two positions.

According to the analyses Campylognathoides would be closely related to Eudimorphodon
Eudimorphodon
Eudimorphodon was a pterosaur that was discovered in 1973 by Mario Pandolfi near Bergamo, Italy and described the same year by Rocco Zambelli. The nearly complete skeleton was retrieved from shale deposited during the Late Triassic , making Eudimorphodon the oldest pterosaur then known...

, to which it is similar in skull, sternum and humerus form. This was confirmed by Padian in 2009, though Padian also pointed out several basal features present in Eudimorphodon but lacking in Campylognathoides. In 2010 an analysis was published by Brian Andres showing that Eudimorphodon together with Austriadactylus
Austriadactylus
Austriadactylus is a genus of "rhamphorhynchoid" pterosaur. The fossil remains were unearthed in Late Triassic rocks of Austria.The genus was named in 2002 by Fabio Marco Dalla Vecchia e.a.. The type species is Austriadactylus cristatus. The genus name is derived from Latin Austria and Greek...

formed a very basal clade, leaving Campylognathoides as the only known member of the Campylognathoididae.

Paleobiology

Traditionally 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 is attributed to Campylognathoides, as to most pterosaurs; in this case supported by the provenance of the finds from marine sediments and the very long wings. Padian however, has suggested that, in view of the stout short teeth, ideal for delivering a piercing bite, the form might well have been a predator of small terrestrial animals instead. The niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...

 of specialised fish eater would then have been filled by Dorygnathus which is five times as common in the layers. The area of the fossil sites was in the early Jurassic located to the northwest of a large island , the Massif of Bohemia, situated in a shallow gulf of the Tethys Sea.

See also

  • Dorygnathus
    Dorygnathus
    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 wingspan, and a relatively small triangular sternum, which is where its flight muscles attached. Its skull...

  • 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...

  • List of pterosaurs
  • Rhamphorhynchus

External links

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