Caulkicephalus

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Caulkicephalus
Temporal range: Early Cretaceous, 130  Ma
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Caulkicephalus trimicrodon.jpg
Life restoration of Caulkicephalus
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Order: Pterosauria
Suborder: Pterodactyloidea
Family: Anhangueridae
Subfamily: Anhanguerinae
Genus: Caulkicephalus
Steel et al., 2005
Species:
C. trimicrodon
Binomial name
Caulkicephalus trimicrodon
Steel et al., 2005

Caulkicephalus is a genus of anhanguerid pterosaur from the Isle of Wight off the coast of England. It lived during the Early Cretaceous period, about 130 million years ago.

Contents

Discovery and naming

Between 1995 and 2003, bone fragments of an unknown pterosaur were found at the Yaverland locality near Sandown. The discoveries were made in or from a brown clay layer from the Wessex Formation of the Wealden Group, stemming from the Early Cretaceous (Barremian age, about 130 million years ago). [1]

In 2005 a new genus was named and described by Lorna Steel, David Martill, David Unwin and John Winch. The type species is Caulkicephalus trimicrodon. The genus name is a translation of "Caulkhead", a traditional nickname for Isle of Wight residents, partially derived from Greek kephale, "head". The specific name, trimicrodon, means "three small teeth", in reference to the dentition. [1]

Description

C.trimicrodon with a human for scale Caulkicephalus size chart.png
C.trimicrodon with a human for scale

The holotype is IWCMS 2002.189.1, 2, 4: three pieces, more or less contiguous, of the front part of a snout. As paratypes have been referred: IWCMS 2002.189.3, a partial posterior skull roof; IWCMS 2003.2, a left quadrate; IWCMS 2003.4, a possible partial jugal; ICWMS 2002.237, a 44 millimeter (1.7 in) long fragment of the first phalanx of the wing finger; IWCMS 2002.234.1-4, four contiguous fragments of a first phalanx, together measuring 245 millimeters (9.6 in) long; IWCMS 2002.233, a possible distal end, 64 millimeters (2.5 in) long, of a second phalanx; IWCMS 2002.236, a fragment of the shaft of possibly the fourth phalanx; and IWCMS 2003.3, a probable fragment of a hindlimb bone. The fossils have only been slightly compressed. [1]

The snout fragments have a combined length of 290 millimeters (11 in). On the snout top the base of a crest is visible, not quite reaching its rounded tip. The teeth have, apart from some replacement teeth present deep in the jaw, been lost but their number, orientation and size can be inferred from the tooth sockets, which however are partly missing at the right side. These are oval and slightly elevated above the jaw bone. The first two tooth pairs were pointed somewhat to the front; the teeth more to the back pointed more sideways; the most posterior preserved stood perpendicular to the jaw. The teeth increased in size until the third pair which was the largest. The fourth pair was equal to the first but the fifth, sixth and seventh pairs were markedly smaller, less than half in size; it is this feature which is recalled by the specific name. Pairs eight, nine and ten again equalled the first. After a narrow hiatus between the second and third snout fragment four tooth sockets are present at each side of the latter, but these are not placed in opposite pairs. The number of teeth in the upper jaw thus seems to have been at least fourteen. [1]

The smaller sized teeth were placed in a constriction of the snout, which thus had a broader end with larger teeth, a so-called "prey grab", usually interpreted as an adaptation to catch slippery prey such as fish. [1]

The posterior skull fragment, a braincase which is rather damaged, shows on its top the base of a parietal crest, probably pointing towards the back. It seems to have been separate from the snout crest. [1]

Skull reconstruction, showing known areas in white Caulkicepahlus skull recon.png
Skull reconstruction, showing known areas in white

The layer the fossils were found in, does not consist of marine sediments, but contains land plant debris; this is seen as an indication of a more terrestrial habitat. David Martill estimated Caulkicephalus had a wingspan of around 5 meters (16.5 ft). [1]

Classification

Caulkicephalus was by the describers assigned to the Ornithocheiridae in view of the narrowing in the middle of the snout. The snout crest was seen as an indication it belonged to the more general Ornithocheiroidea sensu Unwin, whereas the parietal crest was suggested to have been a synapomorphy, a shared new feature, of the more narrow group of the Euornithocheira. Unique characters of the species itself, its autapomorphies, are the details of its dentition, the downward and backward running suture between the premaxilla and maxilla, and the fact the median ridge of the palate begins (or ends) at the ninth tooth pair. [1]

In 2019 however, several studies have reassigned Caulkicephalus to the family Anhangueridae, specifically to the subfamily Anhanguerinae, sister taxon to both Guidraco and Ludodactylus . [2] [3] [4] The cladogram below is a topology recovered by Rodrigo Pêgas and colleagues in 2019, showing the position of Caulkicephalus within the Anhangueridae. [5]

Anhangueria
Hamipteridae

Hamipterus

Iberodactylus

Anhangueridae

Tropeognathus

Coloborhynchinae

Coloborhynchus

Siroccopteryx

Uktenadactylus

Anhanguerinae

Caulkicephalus

Guidraco

Ludodactylus

Anhanguera

Liaoningopterus

Cearadactylus

Maaradactylus

See also

Related Research Articles

<i>Cearadactylus</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Cearadactylus is a genus of large anhanguerid pterodactyloid pterosaur from the Romualdo Formation of Brazil, South America. Fossil remains of Cearadactylus dated back to the Albian stage of the Early Cretaceous period, about 112 million years ago. The only known species is C. atrox, described and named in 1985 by Giuseppe Leonardi and Guido Borgomanero. The name refers to the Brazilian state Ceará, and combines this with Greek daktylos, "finger", a reference to the wing finger of pterosaurs. The Latin atrox means "frightful", a reference to the fearsome dentition of the species.

<i>Tropeognathus</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Tropeognathus is a genus of large pterosaurs from the late Early Cretaceous of South America. This genus is considered to be a member of the family Anhangueridae, however, several studies have also recovered it within another family called Ornithocheiridae. Both of these families are diverse groups of pterosaurs known for their keel-tipped snouts and large size. Tropeognathus is regarded as the largest pterosaur found in the Southern Hemisphere, only rivaled by the huge azhdarchids. The type and only species is Tropeognathus mesembrinus. Fossil remains of Tropeognathus have been recovered from the Romualdo Formation, which is a Lagerstätte located in the Santana Group of the Araripe Basin in northeastern Brazil.

<i>Siroccopteryx</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Siroccopteryx is an extinct genus of anhanguerid pterodactyloid pterosaur, known from middle Cretaceous sediments in modern-day Morocco. Some researchers, such as David M. Unwin, consider the genus a junior synonym of Coloborhynchus.

<i>Coloborhynchus</i> Genus of anhanguerid pterosaur from the Cretaceous period

Coloborhynchus is a genus of pterodactyloid pterosaur belonging to the family Anhangueridae, though it has also been recovered as a member of the Ornithocheiridae in some studies. Coloborhynchus is known from the Lower Cretaceous of England, and depending on which species are included, possibly the Albian and Cenomanian ages as well. Coloborhynchus was once thought to be the largest known toothed pterosaur, however, a specimen of the closely related Tropeognathus is now thought to have had a larger wingspan.

<i>Ludodactylus</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Ludodactylus is a genus of anhanguerid pterodactyloid pterosaur from the Early Cretaceous period of what is now the Crato Formation of the Araripe Basin in Ceará, Brazil. The type and only species is L. sibbicki. The generic name Ludodactylus refers to the fact that the animal had the combination of teeth and a Pteranodon-like head crest, similar to many toy pterosaurs, and no such creature was known to exist until the discovery of Ludodactylus. However, Ludodactylus is not the only pterosaur known to possess these features, its very close relative Caulkicephalus is another example.

Ornithocheiridae Family of ornithocheiran pterosaurs

Ornithocheiridae is a group of pterosaurs within the suborder Pterodactyloidea. These pterosaurs were among the last to possess teeth. Members that belong to this group lived from the Early to Late Cretaceous periods, around 140 to 90 million years ago.

<i>Mythunga</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Mythunga is a genus of anhanguerid pterosaur from the late Early Cretaceous of Australia. Fossil remains of Mythunga dated back to the Albian stage of the Early Cretaceous, and the animal itself was found to be a close relative of another Australian anhanguerid called Ferrodraco.

<i>Uktenadactylus</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Uktenadactylus is a genus of anhanguerid pterodactyloid pterosaurs from the Lower Cretaceous Paw Paw Formation of Texas, United States and the Wessex Formation on the Isle of Wight, England. Fossil remains of Uktenadactylus dated back to the Early Cretaceous period, from about 125 to 100 million years ago.

Aetodactylus is a genus of targaryendraconian pterosaur. It is known from a lower jaw discovered in Upper Cretaceous rocks of northeastern Texas, United States.

Aussiedraco is a genus of targaryendraconian pterodactyloid pterosaur from the early Cretaceous of Australia.

Barbosania is an extinct genus of crestless targaryendraconian pterosaur from the Cretaceous Romualdo Formation of the Santana Group of northeastern Brazil, dating to the Aptian to Albian.

<i>Guidraco</i> Genus of anhanguerid pterosaur from the Early Cretaceous period

Guidraco is an extinct genus of toothed pterodactyloid pterosaur known from the Early Cretaceous of Liaoning Province, northeast China. According to many recent studies, Guidraco is a member of the group Anhanguerinae, a subfamily belonging to the larger group Anhangueridae.

<i>Lonchodraco</i> Genus of lonchodraconid pterosaur from the Cretaceous period

Lonchodraco is a genus of lonchodraconid pterodactyloid pterosaur from the Late Cretaceous of southern England. The genus includes species that were previously assigned to other genera.

<i>Camposipterus</i> Genus of ornithocheiran pterosaur from the Early Cretaceous

Camposipterus is a genus of pterodactyloid pterosaur from the Early Cretaceous of England. Fossil remains of Camposipterus dated back to the Early Cretaceous, about 112 million years ago.

Anhangueria Clade of ornithocheiran pterosaurs from the Cretaceous period

Anhangueria is a group of pterosaurs belonging to the clade Pteranodontoidea. Fossil remains of this group date back from the Early to Late Cretaceous periods, around 140 to 92.5 million years ago. Anhangueria was named by paleontologists Taissa Rodrigues and Alexander Kellner in a review of Ornithocheirus species in 2013, they defined the clade as a branch-based taxon consisting of all pteranodontoids more closely related to Anhanguera blittersdorffi than to Istiodactylus latidens and Cimoliopterus cuvieri.

<i>Maaradactylus</i> Genus of anhanguerid pterosaur from the Early Cretaceous

Maaradactylus is a genus of anhanguerid pterodactyloid pterosaur known from the Lower Cretaceous period of the Romualdo Formation of northeastern Brazil.

Ornithocheiromorpha Clade of pteranodontoid pterosaurs

Ornithocheiromorpha is a group of pterosaurs within the suborder Pterodactyloidea. Fossil remains of this group date back from the Early to Late Cretaceous periods, around 140 to 92.5 million years ago. Ornithocheiromorphs were discovered worldwide except Antarctica, though most genera were recovered in Europe, Asia and South America. They were the most diverse and successful pterosaurs during the Early Cretaceous, but throughout the Late Cretaceous they were replaced by better adapted and more advanced pterosaur species such the pteranodontids and azhdarchoids. The Ornithocheiromorpha was defined in 2014 by Andres and colleagues, and they made Ornithocheiromorpha the most inclusive clade containing Ornithocheirus, but not Pteranodon.

<i>Iberodactylus</i> Genus of hamipterid pterosaur from the Early Cretaceous

Iberodactylus is a genus of pterodactyloid pterosaurs belonging to the clade Anhangueria, that during the Early Cretaceous lived in the area of present Spain. The type species is Iberodactylus andreui.

<i>Ferrodraco</i> Genus of anhanguerid pterosaur from the Late Cretaceous

Ferrodraco is an extinct genus of anhanguerid pterosaur known from the Late Cretaceous Winton Formation of Queensland, Australia, containing the single species F. lentoni. The species was named after the former mayor of Winton, Graham Thomas ‘Butch’ Lenton. It is the most complete pterosaur fossil from Australia, being known from the holotype specimen AODF 876, consisting primarily of the anterior portion of the skull and dentary, cervical vertebral centra and a partial wing. Its wingspan was estimated to be about 4 meters (13 ft). Ferrodraco was found to have been within the subfamily Ornithocheirinae, as sister taxon to Mythunga. A recent study also recovered Ferrodraco as sister taxon to Mythunga, but both placed within the family Anhangueridae, more specifically within the subfamily Tropeognathinae. Ferrodraco is also the latest surviving member of Anhangueria.

<i>Nicorhynchus</i> Genus of anhanguerid pterosaur from the Cretaceous period

Nicorhynchus is a genus of anhanguerid pterosaur from the Cretaceous period. It contains two species, the type species, N. capito, from the Cambridge Greensand of England, and N. fluviferox from the Kem Kem Group of Morocco. These species were previously assigned to Coloborhynchus.

References

  1. 1 2 3 4 5 6 7 8 Steel, L., Martill, D.M., Unwin, D.M. and Winch, J. D. (2005). "A new pterodactyloid pterosaur from the Wessex Formation (Lower Cretaceous) of the Isle of Wight, England". Cretaceous Research. 26 (4): 686–698. doi:10.1016/j.cretres.2005.03.005.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. Borja Holgado, Rodrigo V. Pêgas, José Ignacio Canudo, Josep Fortuny, Taissa Rodrigues, Julio Company & Alexander W.A. Kellner, 2019, "On a new crested pterodactyloid from the Early Cretaceous of the Iberian Peninsula and the radiation of the clade Anhangueria", Scientific Reports9: 4940 doi : 10.1038/s41598-019-41280-4
  3. Kellner, Alexander W. A.; Caldwell, Michael W.; Holgado, Borja; Vecchia, Fabio M. Dalla; Nohra, Roy; Sayão, Juliana M.; Currie, Philip J. (2019). "First complete pterosaur from the Afro-Arabian continent: insight into pterodactyloid diversity". Scientific Reports. 9 (1): 17875. doi: 10.1038/s41598-019-54042-z . PMC   6884559 . PMID   31784545.
  4. Zhou X., Pêgas R.V., Leal M.E.C. & Bonde N. 2019. "Nurhachius luei, a new istiodactylid pterosaur (Pterosauria, Pterodactyloidea) from the Early Cretaceous Jiufotang Formation of Chaoyang City, Liaoning Province (China) and comments on the Istiodactylidae." PeerJ7:e7688
  5. Rodrigo V. Pêgas, Borja Holgado & Maria Eduarda C. Leal (2019) On Targaryendraco wiedenrothi gen. nov. (Pterodactyloidea, Pteranodontoidea, Lanceodontia) and recognition of a new cosmopolitan lineage of Cretaceous toothed pterodactyloids, Historical Biology, doi : 10.1080/08912963.2019.1690482