Caulkicephalus is a genus of pterosaur, belonging to the Pterodactyloidea, from the Isle of Wight off the coast of England.

 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).

 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.

 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 millimetres long fragment of the first phalanx of the wing finger; IWCMS 2002.234.1-4, four, together 245 millimetres long, contiguous fragments of a first phalanx; IWCMS 2002.233, a possible distal end, 64 millimetres 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.

 The snout fragments have a combined length of 290 millimetres. 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.

 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.

 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.

 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 downwards and backwards running suture between the praemaxilla and maxilla, and the fact the median ridge of the palate begins (or ends) at the ninth tooth pair.

 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 metres (16.5 ft).

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Tags: Вымершие рептилии, Мел, авеметатарзалии, архозавроморфы, архозавры, диапсиды, монофенестраты, орнитохейриды, орнитохейройды, птеранодонтойды, птеродактили, птерозавры

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 Cearadactylus is a genus of large Early Cretaceous (Albian) pterosaurs from South America. The only known species is Cearadactylus 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.

 The holotype is MN 7019-V (earlier CB-PV-F-O93), from the Romualdo Member of the Santana Formation. This fossil, a single skull with a length of 57 centimetres, was discovered on the Araripe plateau in northeastern Brazil. It was traded to Italy in 1983 and bought by Borgomanero for his collection. The skull is severely damaged, especially on the top, and was perhaps reconstructed by the fossil dealer.

 As shown by a later preparation by the Brazilian Museu Nacional, in the first preparation many serious mistakes were made. The fronts of the snout and of the lower jaws were confused leading to a reconstruction in which the anterior part of the head was upside down. The teeth were extensively restored and enlarged until the wider front of the jaws showed very large and robust teeth projecting outwards, forming a sort of "rosette". This kinked upper jaw and its interlocking teeth suggested a piscivourous diet, allowing the animal to keep hold of slippery fish. No crests seemed to be present. The new preparation made clear that a crest was present on the snout and that the rosette was a lot smaller. Many details were discovered that were useful in determining the phylogenetic position of Cearadactylus.

 The wingspan of Cearadactylus was by the describers estimated to have been around 4 metres (13 ft), with a weight of perhaps 15 kilograms (33 lb). Peter Wellnhofer in 1991 estimated a wingspan of 5.5 metres (18 ft).

 Leonardi did abstain from assigning the genus to a family. Wellnhofer created a special family Cearadactylidae, but this concept is no longer used. In 2000 Alexander Kellner concluded that is was related to, but lacking a crest not part of, the Anhangueridae within a larger Pteranodontoidea sensu Kellner. In 2002 David Unwin however stated it was a highly deviant member of Ctenochasmatidae. In 2010 Kellner entered the new information into three existing databases of pterosaur features, to calculate through cladistic analysis the position of Cearadactylus in the phylogenetic tree. Although the three resulting trees differed, all had in common that Cearadactylus was close to the Anhangueridae.

 In 1993 Fabio Marco Dalla Vecchia named a second species, Cearadactylus ligabuei. The specific name honours Giancarlo Ligabue, the director of the Centro Sudi Ricerche Ligabue in Venice. It is based on holotype CCSRL 12692/12713, again a heavily damaged crestless skull, 403 millimetres long. The skull consists of two pieces, the front and the back part, glued together by fossil traders; it is uncertain whether they belong to the same individual or indeed to the same species. Dalla Vecchia was himself not convinced the new species in fact belonged to Cearadactylus, but the skull was not sufficiently unique to base its own genus on yet still too different from known species to be assigned to them, so he created a new species for the genus the fossil most resembled. Later authors have consistently denied the identity referring to the taxon as "Cearadactylus" ligabuei.

 Dalla Vecchia estimated the wingspan at six metres; Kellner, pointing out that the skull is not larger than the C. atrox holotype, at five metres at the most. Dalla Vecchia assigned C. ligabuei to the Cearadactylidae. Kellner concluded it was probably a member of Anhangueridae; Unwin in 2002 even named it Anhanguera ligabuei. Steel e.a. (2005) suggested it was a Coloborhynchus ligabuei.

 Церадактиль (Ceradactylus) – летающий ящер с размахом крыльев 5,5 метров и в длину около 1,5 м. (из которых один череп составляет около 60 см.), обитал в середине мелового периода. Его окаменелости были обнаружены в 1983 г. на территории штата Сеара в Бразилии. Научное описание этого вида сделали Джузеппе Леонарди и Гвидо Боргоманеро в 1985 г.

 Специалисты полагают, что этот ящер, в отличие от других птерозавров, мог не только парить, но и активно взмахивать крыльями. Устройство челюстей и зубов говорит о преимущественно рыбном рационе, причем зубы этого ящера были достаточно большими, редкими, развернутыми наружу (для удержания скользкой добычи) и локализованными в передней части челюстей. На конце морды у церадактиля был небольшой гребень. Вероятно, этот птерозавр селился по берегам крупных рек, озер и морей.

 На суше эти ящеры были неуклюжими и, скорее всего, не могли взлетать с ровной поверхности. В качестве «взлетной площадки» они использовали выступы скал и утесы.

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Tags: Вымершие рептилии, Мел, авеметатарзалии, архозавроморфы, архозавры, диапсиды, монофенестраты, орнитохейройды, птеранодонтойды, птеродактили, птерозавры

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