Cuspicephalus
Encyclopedia
Cuspicephalus is an extinct 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 monofenestratan 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...

 known from Dorset
Dorset
Dorset , is a county in South West England on the English Channel coast. The county town is Dorchester which is situated in the south. The Hampshire towns of Bournemouth and Christchurch joined the county with the reorganisation of local government in 1974...

 in England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

.

Discovery

Cuspicephalus is known from 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...

 MJML K1918, a partial skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

 which is missing the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...

 and dentition
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age...

, preserved on a single slab. It was collected in December 2009 by Steve Etches from Kimmeridge Bay on the Isle of Purbeck
Isle of Purbeck
The Isle of Purbeck, not a true island but a peninsula, is in the county of Dorset, England. It is bordered by the English Channel to the south and east, where steep cliffs fall to the sea; and by the marshy lands of the River Frome and Poole Harbour to the north. Its western boundary is less well...

 coast of Dorset
Dorset
Dorset , is a county in South West England on the English Channel coast. The county town is Dorchester which is situated in the south. The Hampshire towns of Bournemouth and Christchurch joined the county with the reorganisation of local government in 1974...

. This locality is referred to the Autissiodorensis ammonite biozone of the lower part of the Kimmeridge Clay Formation, dating to the early Kimmeridgian
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age or stage in the Late or Upper Jurassic epoch or series. It spans the time between 155.7 ± 4 Ma and 150.8 ± 4 Ma . The Kimmeridgian follows the Oxfordian and precedes the Tithonian....

 stage of 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...

, about 155.7-153 million years ago.

Naming and etymology

Cuspicephalus was first named by David M. Martill and Steve Etches in 2011
2011 in paleontology
-Lobopods:-Arachnids:-Insects:-Newly named jawless vertebrates:-Newly named acanthodian:-Newly named cartilaginous fishes:-Newly named bony fishes:-Newly named lepospondyls:-Newly named temnospondyls:-Newly named lissamphibians:...

 and 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 Cuspicephalus scarfi. The generic name is derived from cuspis, 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...

 for "point", after its pointed rostrum
Rostrum
Rostrum may refer to:* A piece of furniture suitable for holding papers used by a person who is addressing a group; a lectern* Australian Rostrum, an association of Australian public speaking clubs...

, and a Latinised Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 κεφαλή, kephalè, for "head". The specific name honors artist and cartoonist Gerald Scarfe
Gerald Scarfe
Gerald Anthony Scarfe, CBE, RDI, is an English cartoonist and illustrator. He worked as editorial cartoonist for The Sunday Times and illustrator for The New Yorker...

 for his vicious caricatures which mostly have very pointy noses.

Description

The skull is lightly built and has a length of 326 millimetres. It is very elongated, being just 55 millimetres high at the back, and has an triangular profile. Almost half of its length is accounted for by a large skull opening, the fenestra nasoantorbitalis, a confluence of the original fenestra antorbitalis with the bony nostrils. In front of this opening a low and elongated snout is present. The rostral index sensu Naish
Darren Naish
Darren Naish is a vertebrate palaeontologist and science writer. He obtained a geology degree at the University of Southampton and later studied vertebrate palaeontology under British palaeontologist David Martill at the University of Portsmouth, where he obtained both an M. Phil...

 & Martill of this snout, in this case its length divided by its maximum height, is 5.4, the highest value known for any pterosaur. In the snout about eleven or twelve teeth are present; the total for the upper jaw is estimated at twenty-five to thirty. The teeth are largest in front and gradually decline in size towards the back. They have a broad base with an oval cross-section. Perhaps they are pointing outwards to a degree but the deformation of the fossil by compression makes this uncertain.

On top of the skull, behind the snout proper, above the fenestra a longitudinal low bony crest is present. It consists of fibrous bone, vertically directed, which might have formed the base for a much higher crest of soft tissue. The crest starts above the twelfth tooth position; its limit at the back is unknown because of damage but it is considered unlikely that it extended as far as the eyes, the roof of the skull not showing any trace of it. The crest is highest in the (preserved) middle.

Phylogeny

The describers did not perform a cladistic analysis to determine the exact place of Cuspicephalus in pterosaur phylogeny. Using the comparative method, they noticed a resemblance to Germanodactylus
Germanodactylus
Germanodactylus is a genus of dsungaripteroid pterodactyloid pterosaur from Late Jurassic-age rocks of Germany, including the Solnhofen limestone. Its specimens were long thought to pertain to Pterodactylus. Its head crest is a distinctive feature.-Description:Germanodactylus is described as...

. Until recently pterosaurs with a head shape like that of Cuspicephalus would as a matter of course been assigned to the Pterodactyloidea
Pterodactyloidea
Pterodactyloidea forms one of the two suborders of pterosaurs , and contains the most derived members of this group of flying reptiles...

. Today it is known however that more basal groups had comparable heads, so the describers placed Cuspicephalus as a member of the more general Monofenestrata
Monofenestrata
Monofenestrata is an unranked group of pterosaurs that includes the family Wukongopteridae and the superfamily Pterodactyloidea....

.

External link

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