Zhenyuanopterus is a genus of pterosaur which is known from Lower Cretaceous (early Aptian) Yixian Formation of Liaoning, China.

 It has been suggested that Zhenyuanopterus foraged while swimming, trapping prey within its needle-like teeth, a method similar to that of modern Platanista river dolphins, which display a similar dentition. This is a reasonably large pterosaur, with a wingspan of about 4 m (Lü 2010).

 One more interesting thing to say about these pterosaurs – and this isn’t unique to boreopterids but goes for ornithocheirids as well – look how tiny their feet are! It also seems that some ornithocheiroids lack fibulae, but it remains uncertain how widespread this is (among boreopterids, Boreopterus lacks them but this was assumed to be preservational, while Zhenyuanopterus has them). The enormous wings and very small, weak legs of many ornithocheiroids show pretty convincingly that they were predominantly aerial, that they walked little, and that they made a living by grabbing objects while in flight. What a strong contrast to long-legged, relatively short-winged pterodactyloids like the azhdarchids.

 It has been often suggested that this animal is actually the adult of its close relative Boreopterus, which is known to be a juvenile.

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

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 Ikrandraco ("Ikran [a flying creature from Avatar with a crest on the lower jaw] dragon") is a genus of pteranodontoid pterosaur known from Lower Cretaceous rocks in northeastern China. It is notable for its unusual skull, which features a crest on the lower jaw.

 Ikrandraco is based on IVPP V18199, a partial skeleton including the skull and jaws, several neck vertebrae, a partial sternal plate, parts of both wings, and part of a foot. A second specimen, IVPP 18406, has also been assigned to Ikrandraco; it consists of a skull and jaws and the first three neck vertebrae. Both specimens come from the Aptian-age Lower Cretaceous Jiufotang Formation of Liaoning, with an estimated date of 120 million years ago. The type and only described species is I. avatar, a second reference to the movie Avatar. It was described in 2014 by Xiaolin Wang and colleagues.

 Ikrandraco is notable for having a very long, low skull (the height of the back of the skull, at the quadrates, is less than 19% the length of the skull), with a prominent blade-like crest on the underside of the lower jaw and no corresponding crest on the tip of the upper jaw, a crest combination not seen in other pterosaurs to date. The posterior edge of the crest also has a hook-like process. Each side of the upper jaw has at least 21 small cylindrical teeth, and each side of the lower jaw has at least 19. The skull of the type specimen is 286.5 millimetres (11.28 in) long, and the skull of the second specimen is at least 268.3 millimetres (10.56 in) long.

 Wang et al. performed a phylogenetic analysis including Ikrandraco and found it to be a basal pteranodontoid, more derived than Pteranodon but not as derived as the istiodactylids, anhanguerids, and other pteranodontoids.

 Wang et al. interpreted the crest as a possible adaptation for skim fishing, although they did not regard this as the animal's main method of foraging. The hook on the crest may have been an attachment point for a throat pouch for storing food, akin to a pelican. Ikrandraco was an approximate contemporary of distantly related anhanguerids Liaoningopterus gui and Guidraco venator, and all three are regarded as piscivores, but Ikrandraco differed from them in its much smaller and less robust teeth, indicating it had a different niche.

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 Hamipterus is an extinct genus of pteranodontoid pterosaur from the Early Cretaceous of northwestern China. It is known from a single type species, Hamipterus tianshanensis.

 Уникальную находку сделали китайские палеонтологи, изучающие ископаемую фауну хребта Тянь-Шань. Среди десятков скелетов нового вида птерозавров они обнаружили несколько сохранивших свою исходную форму яиц этих рептилий. Ничего подобного ученый мир до сих пор не видел.

 Пять продолговатых яиц небольшого размера стали настоящей сенсацией. До сих пор науке были известны лишь четыре птерозавровых яйца, причем все они в процессе окаменения были смяты в лепешку. Обнаруженные же на южных склонах Тянь-Шаня яйца исключительно хорошо сохранились и внешне напоминают яйца некоторых современных змей и ящериц, рассказали ученые.

 Вместе с ними были обнаружены и остатки по меньшей мере 40 особей нового вида птерозавров, названного Hamipterus tianshanensis. "Большинство окаменелостей оказались относительно нетронутыми, что благоприятствовало сборам полных скелетов этих птерозавров", – рассказал палеонтолог Ван Сяолинь, автор открытия. Как показали его исследования, хамиптерусы достигали четырех метров в размахе крыльев, имели заостренные зубы и удлиненный череп с гребнем на макушке. Кроме того, самцы и самки различались своим внешним видом, являясь довольно редким в каменной летописи примером полового диморфизма. Питались эти птерозавры, по всей вероятности, рыбой.

 "Данные окаменелости проливают свет на репродуктивную стратегию, онтогенез и поведение птерозавров, – констатируют авторы исследования. – Они демонстрируют половой диморфизм, благодаря которому самцы и самки отличались размерами гребня, его формой и прочностью... Мы полагаем, что эти новые птерозавры образовывали колонии и обладали стайным поведением, которое, возможно, являлось общим трендом, по крайней мере, для птеродактилоидных птерозавров".

 Директор Института палеонтологии позвоночных и палеоантропологии Китайской академии наук Чжунхэ Чжоу назвал место находки Hamipterus tianshanensis "самым важным местонахождением птерозавров изо всех когда-либо найденных".

 Исходя из характера отложений, исследователи полагают, что крупная колония птерозавров была уничтожена сильным штормом, разразившимся в этих местах в начале мелового периода, около 120 млн лет назад. До этой катастрофы летающие ящеры большой шумной колонией населяли окрестности живописного озера.

 "Это настоящий почетный трофей, который может считаться одним из лучших среди известных находок птерозавров. Он превращает эти места в основной район для исследований этих животных, – рассказал доктор Дэйв Хон. – Имеющиеся данные, естественно, на сегодняшний день далеко не полны, но сам факт находки вместе остатков многочисленных особей и яиц зафиксирован впервые в истории".

 По предварительным оценкам, в этих местах могут быть найдены остатки и других меловых позвоночных, в том числе и птиц.

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 Tropeognathus is a genus of large pterosaurs from the late Cretaceous Period of South America. It was member of the Ornithocheiridae (alternately Anhangueridae), a group of pterosaurs known for their keel-tipped snouts, and was closely related to species of the genus Anhanguera. It is known primarily for the species Tropeognathus mesembrinus, though a second species, Tropeognathus robustus, has been named in the genus.

 In the 1980s the German Bayerische Staatssammlung für Paläontologie und historische Geologie at Munich acquired a pterosaur skull from Brazilian fossil dealers, that had probably been found in Ceará, in the Chapade do Araripe. In 1987 it was named and described as the type species Tropeognathus mesembrinus by Peter Wellnhofer. The generic name is derived from Greek τρόπις, tropis, "keel", and γνάθος, gnathos, "jaw". The specific name is derived from Koine mesembrinos, "of the noontide", "southern", in reference to the provenance from the Southern hemisphere.

 The holotype, BSP 1987 I 46, was discovered in a layer of the Romualdo Member of the Santana Formation, dating from the Aptian-Albian. It consists of a skull with lower jaws. A second specimen was referred by André Jacques Veldmeijer in 2002: SMNS 56994, consisting of partial lower jaws. In 2013, Alexander Wilhelm Armin Kellner referred a third, larger, specimen: MN 6594-1, a skeleton with skull, with extensive elements of all body parts, except the tail and the lower hindlimbs.

 After Tropeognathus mesembrinus was named by Peter Wellnhofer in 1987 other researchers tended to consider it part of several other genera, leading to an enormous taxonomic confusion. It was considered an Anhanguera mesembrinus by Alexander Kellner in 1989, a Coloborhynchus mesembrinus by Veldmeijer in 1998 and a Criorhynchus mesembrinus by Michael Fastnacht in 2001. In 2001, David Unwin referred the Tropeognathus material to Ornithocheirus simus, making Tropeognathus mesembrinus a junior synonym, though he again reinstated a Ornithocheirus mesembrinus in 2003. Veldmeijer in 2003 accepted that Tropeognathus and Ornithocheirus were cogeneric but rejecting O. simus as the type species of Ornithocheirus in favor of O. compressirostris (named Lonchodectes by Unwin), used the names Criorhynchus simus and Criorhynchus mesembrinus. In 2000, Kellner again began to use the original name Tropeognathus mesembrinus. In 2013, Taissa Rodrigues and Kellner concluded Tropeognathus to be valid, and containing only T. mesembrinus.

 In 1987 Wellnhofer named a second species, Tropeognathus robustus, based on specimen BSP 1987 I 47, a more robust lower jaw. Today, this is no longer considered cogeneric with Tropeognathus mesembrinus.

 Tropeognathus mesembrinus is known to have reached wingspans of up to 8.2 m (27 ft), as can be inferred from the size of specimen MN 6594-1. T. mesembrinus bore distinctive convex "keeled" crests on its snout and underside of the lower jaws. The upper crests arose from the snout tip and extended back to the fenestra nasoantorbitalis, the large opening in the skull side. An additional, smaller crest projected down from the lower jaws at their symphysis ("chin" area). While many ornithocheirids had a small, rounded bony crest projecting from the back of the skull, this was particularly large and well-developed in Tropeognathus. The first five dorsal vertebrae are fused in to a notarium. Five sacral vertebrae are fused into a synsacrum. The third and fourth sacral vertebrae are keeled. The front blade of the ilium is strongly directed upwards.

 In 1987 Wellnhofer assigned Tropeognathus to a Tropeognathidae. This concept was not adopted by other workers; Brazilian researchers place Tropeognathus mesembrinus in the Anhangueridae, their European colleagues tend to prefer the Ornithocheiridae.

 Тропеогнат был одним из крупнейших птерозавров мелового периода и ярким представителем группы Ornithocheiridae, отличавшихся своим крупными килеобразными выростами на конце челюстей от других птеродактилей.

 Впервые тропеогнат был описан в 1980 г., когда немецкий музей Bayerische Staatssammlung fur Palaontologie und Historische Geologie выкупил у бразильских продавцов окаменелостей огромного летающего ящера, который был обнаружен в местонахождении Сеара на севере Бразилии. Вид в 1987 г. получил типовое наименование Tropeognathus mesembrinus.

 Тропеогнаты достигали достаточно внушительных размеров: размах крыльев этих ящеров достигал 8,2 метров. Как отмечалось ранее, отличительная черта орнитохейрид: килевые гребни на конце морды, верхний из которых шел от конца челюсти и до начала анторбитального отверстия (antorbitalis fenestra). Нижний гребень был немного меньше и представлял собой расширение подбородочной кости.

 Грудные позвонки у тропеогната были мощными и были слиты в единый костный выступ, поддерживающий объемные мышечные маховые связки. Крестцовые позвонки также слиты в одно костное образование.

 В сериале ВВС «Прогулки с динозаврами» одна из серий посвящена жизни летающего гиганта Ornithocheirus, который, на самом деле, является представителем Tropeognathus mesembrinus. В сериале использовались данные по окаменелостям летающего ящера, обнаруженного в 1998 г. на севере Бразилии. Расчетные показатели свидетельствовали о том, что этот бразильский гигант мог достигать размаха крыльев в 12 метров и был весом до 100 кг, что делало его одним из самых крупных обнаруженных птерозавров.

 Однако типовые экземпляры Ornithocheirus не превышают 6 метров в размахе крыльев. Окаменелости из Бразилии еще находились на стадии изучения и только в 2012 г. Дэйв Мартилл и Хайнц Петер Бредов опубликовали окончательную оценку размеров найденной особи, согласно которой этот экземпляр тропеогната не мог превышать 8,2 м. в размахе крыльев. Х.П. Бредов пояснил: «Вероятно, при работе над сериалом были использованы самые максимальные из возможных показателей, чтобы сериал казался более захватывающим и зрелищным».

 У этих летающих ящеров был достаточно развит половой диморфизм: самки были мельче в размерах и имели менее выраженные выросты на челюстях.

 Анализ строения нижних конечностей тропеогната свидетельствует о том, что этот птерозавр вполне был способен перемещаться по плоской поверхности, а не только по скальным выступам и утесам, как большинство других птерозавров.

 Длинные, острые и изогнутые зубы, разного размера говорят о рыбоядной специализации тропеогната. Предполагается, что ящер парил над поверхностью воды, вылавливая рыбу из верхних слоев океана, причем в данном случае, выступающие гребни на челюстях служили своеобразным стабилизатором при полете.

 В меловом периоде птерозавры, в целом, характеризуются увеличением своих размеров, размах крыльев некоторых видов достигает поистине неимоверных величин, в то же самое время видовое разнообразие летающих ящеров становится очень разнообразным. Поэтому тропеогнат, наряду с гигантскими аждархидами, является ярким представителем гигантизма и разнообразия летающих ящеров в меловом периоде.

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

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

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 Ludodactylus was a genus of pterodactyloid pterosaurs from the Aptian-age Lower Cretaceous Crato Formation of Ceará,Brazil. The genus was named by Eberhard Frey et al. in 2003 and contains one known species, Ludodactylus sibbicki. The name is derived from Latin ludus, "play" and Greek daktylos, "finger". Ludus refers to the fact, long lamented by paleontologists, that many toy pterosaurs combined teeth with a Pteranodon-like head crest, while no such creature was known to exist — however Ludodactylus shows exactly this combination of features. "Dactylus", in reference to the characteristic long wing finger, has been a common element in the names of pterosaurs since the first known was named Pterodactylus. The specific name"sibbicki" is an homage to the paleoartist John Sibbick.

 Ludodactylus is based on holotype SMNK PAL 3828, a skull missing part of the head crest, that was removed from the plate before the fossil was illegally sold. Unlike other ornithocheirids, it had no premaxillary crest on the snout, but did have a crest at the back of the skull. Frey et al. interpreted the deep mandible as a crest on the lower jaws. Trapped between the rami of the mandible is a yucca leaf; Frey suggested that the animal got it caught in its beak and unsuccessfully tried to dislodge it (the edge of the leaf is frayed), and then possibly died from starvation or a complication of starving. The skull would have been more than 66 cm (26 in) long.

 Frey et al. in 2003 classified Ludodactylus in the family Ornithocheiridae. In 2007 Frey, had reconsidered the validity of Ludodactylus, suggesting that it may represent the same animal as, and be a junior synonymof, Brasileodactylus. However, Andres & Myers (2013), in a large cladistic analysis of pterosaurs, found Ludodactylus to be slightly more closely related to ornithocheirids and anganguerids than to Brasileodactylus. In the analysis of Andres and Myers,Ludodactylus is classified just outside Ornithocheiridae and Anhangueridae as a derived member of the more inclusive group Pteranodontoidea.

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 Liaoningopterus, sometimes misspelled "Liaoningopteryx", was a genus of ornithocheirid pterodactyloid pterosaur from the Barremian-Aptian-age Lower Cretaceous Jiufotang Formation of Chaoyang, Liaoning, China.

 The genus was named in 2003 by Wang Xiaolin and Zhou Zhimin. The type species is Liaoningopterus gui. The genus name is derived from Liaoning and a Latinised Greek pteron, "wing". The specific name honours Professor Gu Zhiwei, an invertebrate specialist who has pioneered the study of the Jehol Biota.

 The genus is based on holotype IVPP V-13291, a crushed partial skull and skeleton including the jaws, teeth, a cervical vertebra, and bones of the finger supporting the wing. It was a large pterosaur — the largest known from China at the time of description — with a skull length estimated at 61 cm (24 in), and a wingspan estimated at five metres (16.4 ft). The skull was long and low, bearing low crests close to the tip of the beak on both lower and upper jaws. The snout crest was twelve centimetres long, was symmetrical in form and had a maximum height of seventeen millimetres. The edge of the upper jaw was very straight. The teeth were only found at the anterior end of the jaws. They were elongated but robust, generally increasing in size from the back to the front. The fourth tooth in the upper jaw is with a length of 81 millimetres the largest known for any pterosaur. It is exceptional in size compared to the other teeth of Liaoningopterus also, the longest tooth in the lower jaw having a length of 41 millimetres. Tooth length in the specimen is very variable, which the authors explained by the presence of recently erupted replacement teeth. There were twenty pairs of teeth in the upper jaws and thirteen or fourteen pairs in the lower jaws.

 The preserved cervical vertebra has a centrum length of 46 millimetres and a centrum height of 34 millimetres. From the wing bones pieces of the first phalanx can be recognised which had an estimated total length of about fifty centimetres.

 The authors described Liaoningopterus as being probably a piscivore, due to the long, pointed snout.

 Wang classified Liaoningopterus as a member of the Anhangueridae, mainly because of the crests. This opinion was restated by him in 2005. In 2006 Lü Junchang published a cladistic analysis showing Liaoningopterus to be a basal member of the Anhangueridae; in 2008 an analysis by Ji Qiang had Liaoningopterus in a trichotomy with Anhanguera and Tropeognathus.

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 Istiodactylus is a genus of a medium sized pterosaurs from the early Cretaceous period.

 Istiodactylus were moderately large pterosaurs. Correcting earlier estimates of a length of fifty-six centimetres, Mark Paul Witton in 2012 concluded that the skull of one specimen, NHMUK R3877, was forty-three centimetres long. The maximum wingspan was probably about 4.3 metres (14.1 ft), making the largest individuals roughly half the size of the largest Pteranodon. Because of the flat, rounded shape of the snout, Istiodactylus is sometimes referred to as a "duck-billed pterosaur". However, unlike ducks, they had teeth. These triangular teeth were laterally compressed, an adaptation for slicing flesh, and interlocked tightly in the closed jaws. The skull was relatively short, with most teeth concentrated in the blunt front tip of the jaws. Witton's 2012 study proposed that Istiodactylus were primarily scavengers.

 In 1887 Harry Govier Seeley named the remains of a fossil pelvis discovered on the Isle of Wight, Ornithodesmus cluniculus, thinking it was a bird. In 1901 he considered that it might have been a pterosaur. In 1913 Reginald Walter Hooley named a second species, Ornithodesmus latidens, for some definitively pterosaurian material, found in the Vectis Formation. The holotype was BMNH R 0176, a partial skeleton. The specific name means "broad tooth" in Latin.

 The type species of the genus Ornithodesmus, however, was in the 1980s discovered to be based on bones belonging to a dinosaur, which meant a new genus had to be named for O. latidens. This species was assigned to its own genus Istiodactylus by Stafford Howse, Andrew Milner, and David Martill in 2001. The genus name is derived from Greek istion, "sail" and daktylos, "finger", referring to the fact that the wing of pterosaurs is formed by a membrane attached to a wingfinger.

 Howse et al. in 2001 created for Istiodactylus its own family Istiodactylidae.

 In 2006 a second species, I. sinensis from China, has been named, its specific name referring to China. Its holotype is NGMC 99-07-011, a partial skeleton of a subadult individual. It was much smaller than I. latidens, its dimensions being 63% of the larger species, thus about a quarter in weight. In 2006 Lü Jun-Chang et al. concluded I. sinensis was a junior synonym of the istiodactylid Nurhachius. Mark Witton has proposed it may be a synonym of Liaoxipterus.

 Istiodactylidae is a small family of pterosaurs. This family was named in 2001 after the type genus Istiodactylus was discovered not to be a member of the genus Ornithodesmus.

 Remains of taxa that can be confidently assigned to Istiodactylidae have been found in the UK and China, in rocks dating from the Early Cretaceous period (Barremian to Aptian stage). Arbour and Currie (2011) described Canadian Gwawinapterus beardi as a member of Istiodactylidae living in the late Cretaceous (upper Campanian stage); however, Witton (2012) suggested the tooth replacement pattern in this animal does not match that of pterosaurs, suggesting that the species might be non-pterosaurian. Additional research suggested that the species was in fact a fish. The earliest known species might be Archaeoistiodactylus linglongtaensis, from the Middle Jurassic of China; however, it also has been suggested that the holotype specimen of this species might actually be a poorly preserved specimen of Darwinopterus. Hongshanopterus, a supposed istiodactylid from China, has been reclassified as a non-istiodactylid member of Ornithocheroidea of uncertain phylogenetic placement by Witton (2012).

 Istiodactylids were medium sized pterosaurs with flat, rounded jaws similar to that of a duck. They had small teeth lining their jaws, however.

 Крылатые рептилии мелового периода были не хищниками, а самыми настоящими падальщиками наподобие современных грифов. Питались они главным образом мертвыми динозаврами.

 Неожиданное открытие сделал доктор Марк Уиттон из Портсмутского университета. Он решил тщательно изучить останки птерозавра Istiodactylus latidens, найденного в 1904 году на острове Уайт, и с тех пор лежавшего на витрине Лондонского музея естественной истории.

 Поскольку до сих пор изученными оставались лишь черепная коробка и ветви челюсти этого животного, у палеонтологов сложилось мнение о его узкой, низкой и длинной голове. Как показало новое исследование, голова истиодактилуса, напротив, была высокой, широкой и короткой. При этом кости обеспечивали надежное крепление чудовищной шейной мускулатуре, позволявщей крылатому ящеру легко отрывать куски плоти с туш крупных животных.

 В то время как зубы Istiodactylus latidens были острыми и приспособленными для разрезания мяса, его скулы оказались неожиданно тонкими. Их толщина едва достигает шести миллиметров при общей высоте черепа до 45 сантиметров. Ящер легко мог сломать себе кости, если бы вступил в схватку даже с не слишком сильным противником, сообщает The Daily Mail. Именно это обстоятельство позволило доктору Уиттону сделать предположение о том, что добыча истиодактилусов никогда не сопротивлялась, а просто лежала на одном месте.

 "Современные птицы-падальщики имеют схожую конструкцию черепа, обладающую как сильными, так и слабыми компонентами. Поедание мертвой плоти позволяет птицам-падальщикам практически полностью контролировать процесс питания, поэтому они могут позволить себе иметь несколько слабых участков, расположенных вдоль челюсти, не беспокоясь о том, что их можно сломать при укусе, – рассказал палеонтолог. – Широкий и высокий череп Istiodactylus latidens позволяет прикрепить мощный набор шейных мышц, что указывает на сильную шею, которая является еще одним общим качеством птиц-падальщиков, которые используют свои сильные шеи, чтобы растаскивать части трупа. Если сопоставить данные обстоятельства с режущими зубами, то все эти свойства являются хорошим доказательством падалеядного образа жизни, который вели эти животные".

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 Guidraco (Chin. gui (鬼) "malicious ghost" + Lat. draco "dragon") is an extinct genus of toothed pterodactyloid pterosaur known from the Early Cretaceous of Liaoning Province, northeast China.

 Guidraco is known only from the holotype IVPP V17083, an articulated partial skeleton consisting of a nearly complete skull, lower jaws and a series of four, second to fifth, cervical vertebrae. It was collected at Sihedang near Lingyuan City in the Liaoning Province from the Jiufotang Formation, dating to the Aptian stage of the Early Cretaceous, about 120 million years ago.

 Guidraco was first described and named by Wang Xiaolin, Alexander W.A. Kellner, Jiang Shunxing and Cheng Xin in 2012 and the type species is Guidraco venator. The generic name is derived from Chinese gui (鬼), "malicious ghost", and from Latin draco, "dragon". The specific name means "hunter" in Latin.

 The holotype skull of Guidraco has a length of thirty-eight centimetres. It is very elongated with a hollow profile but not very pointed as the upper edge and the line of the jaw run nearly parallel over most of their length. The ensuing relative robustness of the snout is reinforced by a short main skull opening, a fenestra nasoantorbitalis with just a quarter of skull length, and a lower jaw equalling the rostrum in depth. The snout lacks a crest. Above the eye sockets however, the line of the top of the snout curves steeply upwards, resulting in a very large crest on the frontals, as high as the posterior part of the skull is deep, ending in a rounded top. Due to the angling of the skull roof the crest slightly points forwards and its base extends to the back of the roof; however, the parietal is not part of it. In front of the crest large impressions of soft tissue are visible but these are plant remains. Further diagnostic features of the skull include an infratemporal fenestra with a narrow lower end, and a jugal of which the front branch extends no further than the front edge of the fenestra nasoantorbitalis.

 The teeth of Guidraco are very distinctive. Of the twenty-three teeth of the upper jaw the first is long and very narrow, pointing nearly horizontally forward. The next three teeth are enormous in size, very long, robust, pointed and slightly recurved. They gradually point more downwards. These are followed by a series of three medium-length downward-pointing straight teeth, of which the middle one, the sixth, is the shortest. The remaining thirteen teeth constitute a long row of small elements gradually diminishing in size. This arrangement is mirrored by the eighteen teeth of the lower jaw. Here however, a forward pointing tooth is lacking. The first four teeth are of great size, even longer than their counterparts of the upper jaw. Next is a series of three straight teeth of medium height, followed by a row of eleven increasingly smaller elements for a grand total in the head of eighty-two teeth. With the fossil, the beak is closed and due to their extreme length the front teeth extend far beyond the upper and lower edges of the head, the protruding parts being up to twice as long as the depth of the snout or lower jaw. The teeth can also be divided into two types according to their built: the first nine teeth of the upper jaw and eight teeth of the lower jaw have vertical ridges on the back of their enamel; the back teeth have a uniformly smooth enamel and thickened crown bases, giving them a more triangular outline.

 Though not having the form of a true rosette because the jaw ends were not expanded, the intermeshing front teeth functioned as a "prey grab" to catch slippery animals; the describers therefore consider Guidraco to have been a fish-eater.

 The neck vertebrae are moderately elongated, keeled and possess large pneumatic openings on their sides, the access by which the air sac of the neck could enter their hollow interiors. The axis bears a spiked spine.

 Guidraco was by the describers assigned to the Pteranodontoidea sensu Kellner. A phylogenetic analysis found it to be the sister taxon of the Brazilian Ludodactylus, the two species together forming a clade that was closely related to the Istiodactylidae and the Anhangueridae. The fact that a Chinese form is closely related to a South-American species would indicate a large faunal interchange between continents in this period.

 Китайская академия наук на днях опубликовала документы, согласно которым на северо-востоке страны ученые обнаружили останки птерозавра редкого типа, имевшего длинные зубы устрашающего вида.

 Согласно опубликованным фотографиям, доисторическая летающая рептилия имела мощные челюсти и крупные резцовые зубы. Палеонтологи говорят, что найденный вид является довольно близким биологическим родственником вида Ludodactylus, останки которого в прошлом были обнаружены учеными на территории современной Бразилии.

 Китайский палеонтолог Вон Сяолин говорит, что рядом с останками древнего ящера были найдены также и останки рыбы, что может свидетельствовать об употреблении в пищу этой рыбы незадолго до смерти птерозавра. Новый вид птерозавра получил научное название Guidraco venator.

 Согласно данным исследователей, рептилия обитала на нашей планете в ранний меловой период - как раз в расцвет эпохи динозавров. Останки ящера были найдены на территории современной китайской провинции Ляонин, где ранее уже находили останки летающих ящеров. 

 Исследователи считают, что родство с бразильским птерозавром объясняется тем, что в ранний меловой период Азия и Южная Америка были расположены гораздо ближе друг к другу и мигрировать летающим ящерам с одного континента на другой было несложно. И тем не менее, считается, что впервые летающие ящеры появились именно в Азии, а уже оттуда распространились в другие регионы.

 По предположению ученых, Guidraco venator вымер из-за нехватки пищи, а  точнее из-за высокой конкуренции с другими, более сложноорганизованными видами.

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 Geosternbergia from the Late Cretaceous geological period of North America, was one of the largest pterosaur genera and had a wingspan of up to 7.25 metres (23.8 ft).

 Geosternbergia was among the largest pterosaurs, with the wingspan of most adults ranging between 3 and 6 meters (9.8–19.6 ft). While most specimens are found crushed, enough fossils exist to put together a detailed description of the animal. Geosternbergia is distinguished from Pteranodon mainly by its upright-crest. The lower jaw of G. sternbergi was 1.25 meters (4 ft) long.

 The most distinctive characteristic of Geosternbergia is its cranial crest. These crests consisted of skull bones (frontals) projecting upward and backward from the skull. The size and shape of these crests varied due to a number of factors, including age, gender, and species. Male G. sternbergi, the older species of the two described to date, had a larger vertical crest with a broad forward projection, while G. maysei had a short, rounded vertical crest and was generally smaller. Females of both species were smaller and bore small, rounded crests. The crests were probably mainly display structures, though they may have had other functions as well.

 It was collected by George F. Sternberg in 1952 and described by John Christian Harksen in 1966, from the lower portion of the Niobrara Formation. It was older than Pteranodon longiceps and is considered by Bennett to be the direct ancestor of the later species.

 Geosternbergia fossils are known from the Niobrara and Sharon Springs Formations of the central United States. Geosternbergia existed as a group for more than four million years during the late Coniacian - early Campanian stages of the Cretaceous period. The genus is present in the lower the Niobrarra Formation except for the upper two; in 2003, Kenneth Carpenter surveyed the distribution and dating of fossils in this formation, demonstrating that Geosternbergia sternbergi existed there from 88-85 million years ago, while the species later named G. maysei existed between 81.5 and 80.5 million years ago.

 Geosternbergia was traditionally considered a species, or occasionally subgenus, of the similar pterosaur Pteranodon, in most major studies of pteranodontians through the 1990s. However, a 2010 review of the group by A.W.A. Kellner suggested that Pteranodon sternbergi was different enough from P. longiceps to belong in a distinct genus, to which Kellner also referred a new species, Geosternbergia maysei. Earlier, pterosaur researcher Chris Bennett had considered the G. maysei specimen an adult male P. longiceps.

 Adult Geosternbergia specimens may be divided into two distinct size classes, small and large, with the large size class being about one and a half times larger than the small, and the small being twice as common as the large. Both size classes lived alongside each other, and while researchers had previously suggested that they represent different species, Christopher Bennett showed that the differences between them are consistent with the concept that they represent females and males, and that Geosternbergia species were sexually dimorphic. Skulls from the larger size class preserve large, upward and backward pointing crests, while the crests of the smaller size class are small and triangular. Some larger skulls also show evidence of a second crest that extended long and low, toward the tip of the beak, which is not seen in smaller specimens.

 The gender of the different size classes was determined, not from the skulls, but from the pelvic bones. Contrary to what may be expected, the smaller size class had disproportionately large and wide-set pelvic bones. Bennett interpreted this as indicating a more spacious birth canal, through which eggs would pass. He concluded that the small size class with small, triangular crests represent females, and the larger, large-crested specimens represent males.

 Note that the overall size and crest size also corresponds to age. Immature specimens are known from both females and males, and immature males often have small crests similar to adult females. Therefore, it seems that the large crests only developed in males when they reached their large, adult size, making the gender of immature specimens difficult to establish from partial remains.

 The fact that females appear to have outnumbered males two to one suggests that, as with modern animals with size-related sexual dimorphism, such as sea lions and other pinnipeds, Geosternbergia might have been polygynous, with a few males competing for association with groups consisting of large numbers of females. Similar to modern pinnipeds, Geosternbergia may have competed to establish territory on rocky, offshore rookeries, with the largest, and largest-crested, males gaining the most territory and having more success mating with females. The crests of male Geosternbergia would not have been used in competition, but rather as "visual dominance-rank symbols", with display rituals taking the place of physical competition with other males. If this hypothesis is correct, it also is likely that male Geosternbergia played little to no part in rearing the young; such a behavior is not found in the males of modern polygynous animals who father many offspring at the same time.

 The Pteranodontidae are a family of large pterosaurs of the Cretaceous Period of North America.

 The family was named in 1876 by Othniel Charles Marsh. Pteranodontids had a distinctive, elongated crest jutting from the rear of the head (most famously seen in Pteranodon itself). The spectacularly-crested Nyctosaurus is sometimes included in this family, though usually placed in its own family, the Nyctosauridae (Nicholson & Lydekker, 1889).

 Modern researchers differ in their use of the concept. S. Christopher Bennett and Alexander Kellner have concluded that Nyctosaurus was not a pteranodontid. In 1994 Bennett defined a clade Pteranodontidae, also including species of the Anhangueridae. However, this definition has not been accepted by other workers. Alexander Kellner, for example, named several additional species for specimens previously classified as Pteranodon, and placed P. sternbergi in a distinct genus, Geosternbergia. Kellner re-defined Pteranodontidae as the most recent common ancestor of Pteranodon longiceps, Geosternbergia sternbergi and Dawndraco kanzai, and all of its descendants. This clade possibly includes the nyctosaurids. Analyses by David Unwin did indicate a close relationship between Pteranodon and Nyctosaurus, and he used the name Pteranodontia for the clade containing both.

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 Coloborhynchus is a genus in the pterosaur family Ornithocheiridae, and is known from the Lower Cretaceous of England (Albian age, 98 million years ago), and possibly the Aptian age (112-99 million years ago) of Brazil and Texas, depending on which species are included.

 The type specimen of Coloborhynchus is known only from a partial upper jaw. Therefore, according to Rodrigues and Kellner's 2008 re-evaluation on Coloborhynchus clavirostris, it can only be differentiated from its relatives based on its unique combination of tooth socket positions. In Coloborhynchus, the two front teeth pointed forward and were higher on the jaw than the other teeth, while the next three pairs of teeth pointed to the sides. The final two (preserved) pairs of teeth pointed downward. Finally, a unique oval depression was located below the first pair of teeth.

 Like the related Anhanguera and Uktenadactylus, the tip of the snout flared out into a wider rosette, in contrast to the narrow posterior jaws. However, whereas the rosettes of species typically assigned to Anhanguera were rounded and spoon-shaped, those of Сoloborhynchus were robust and box-shaped.

 Also like its close relatives, Coloborhynchus had a keel-shaped crest on the front of its jaws, though it was broad and thinned from base to top, rather than the uniformly thin crests of its relatives. This kind of thickened crest is also seen in Siroccopteryx moroccensis, which may be its closest relative or a member of the same genus. It also had a straight, rather than curved, front margin, unlike its relatives, and begins at the tip of the snout, rather than further back as in other species.

 A second specimen showing all of these same unique features was reported to Brazilian paleontologist Alexander Kellner by Darren Naish in 2007, and likely represents a second specimen of C. clavirostris, though it has not yet been described.

 The possible species Coloborhynchus capito represents the largest known ornithocheirid, and indeed the largest toothed pterosaur known. A referred specimen from the Cambridge Greensand of England described in 2011 consists of a very large upper jaw tip which displays the tooth characteristics that distinguish C. capito from other species. The jaw tip is nearly 10 cm tall and 5.6 cm wide, with teeth up to 1.3 cm in base diameter. If the proportions of this specimen were consistent with other known species of Coloborhycnhus, the total skull length could have been up to 75 cm, leading to an estimated wingspan of 7 metres (23 ft).

 Like many ornithocheiroid pterosaurs named during the 19th century, Coloborhynchus has a highly convoluted history of classification. Over the years numerous species have been assigned to it, and often, species have been shuffled between Coloborhynchus and related genera by various researchers.

 In 1874 Richard Owen, rejecting the creation by Harry Govier Seeley of the genus Ornithocheirus, named a species Coloborhynchus clavirostris based on holotype BMNH 1822, a partial snout from the Hastings Beds of the Wealden Group of East Sussex, England. The genus name means "maimed beak", a reference to the damaged and eroded condition of the fossil; the specific name means "key snout", referring to its form in cross-section. Owen also reclassified Ornithocheirus cuvieri and O. sedgwickii as species within the genus Coloborhycnhus, though he did not designate any of these three as the type species. Owen considered the defining trait of the genus to be the location of the front tooth pairs high on the side of the upper jaws. However, in 1913 Reginald Walter Hooley concluded that this location was an artefact of the erosion and that the genus was indistinguishable from Criorhynchus simus, the second genus and species Owen erected in 1874. Hooley also ignored Owen's re-assignment of the two former Ornithocheirus species, leaving them in that genus. In 1967, Kuhn agreed with Hooley that Coloborhynchus clavirostris was a synonym of Criorhynchus simus. Furthermore, Kuhn was the first to formally designate C. clavirostris as the type species of the genus, rather than one of the Ornithocheirus species. Most later researchers followed these opinions, regarding Coloborhynchus as invalid relative to Criorhynchus.

 This changed in 1994 when Yuong-Nam Lee named Coloborhynchus wadleighi for a snout found in 1992 in the Albian age Paw Paw Formation Texas. The revival of the genus meant that of several related species, then assigned to other genera, had to be re-evaluated to determine whether or not they actually belonged to Coloborhynchus. In 2008, Taissa Rodrigues and Alexander Kellner re-formulated the key features of Coloborhynchus, again based mainly on the unique positions of the tooth sockets. Rodrigues and Kellner argued that Lee's C. wadleighi, which possessed some differences in the skull and teeth from C. clavirostris, and from an earlier time period, belonged in its own genus, which they named Uktenadactylus.

 A partial lower jaw originally named Tropeognathus robustus from the Romualdo Member of the Santana Formation in Brazil was assigned to Coloborhycnhus in 2001 by Fastnacht, as Coloborhynchus robustus. In 2002, David Unwin supported this position, and also synonymized the more well-known species Anhanguera piscator with C. robustus. Rodrigues and Kellner disagreed with this classification, however, noting that both did not possess the unique straightened crest beginning at the snout tip, or sideways pointed teeth, of C. clavirostris. Instead, Rodrigues and Kellner regarded both Anhanguera robustus and Anhanguera piscator as valid species of Anhanguera.

 Another Brazilian species from the Romualdo Member was named Coloborhynchus speilbergi by Veldmeijer in 2003. It shares one or two characters in common with C. clavirostris (such as a flattened upper surface of the snout), though Rodrigues and Kellner regarded them as dubious, and noted that they are also present in related species and so are not unique to Coloborhynchus. Rodrigues and Kellner also noted that C. speilbergi didn't have as high a tooth row (exposing the palate) as the type species. Its crest is also very thin, similar to Anhanguera, to which genus Kellner assigned it in 2006. Similarly, Kellner excluded C. araripensis (formerly assigned to the genus Santanadactylus) from the genus, based on lack of comparable diagnostic features. Unwin, in 2001, assigned the species Siroccopteryx moroccensis to Coloborhycnhus, based on its similarity to C. wadleighi (aka Uktenadactylus). Kellner, who regarded Uktenadactylus as a distinct genus in 2008, also regarded Siroccopteryx as distinct, and noted that like the other species assigned to Coloborhynchus, lacked its unique characteristics of the tooth row, a position also supported by Fastnacht in 2001.

 Finally, Unwin (in 2001) also re-assigned the two other species from the Cambridge Greensand to Coloborhycnhus: C. capito and C. sedgwickii, the second of which being one of the original members of the genus according to Richard Owen in 1874. According to Kellner, C. capito is too incomplete to fully compare to C. claviraostris, and its precise classification is open to debate. He noted that C. sedgwicki does not possess the unique features of C. clavirostris (in fact it lacks a crest altogether), and may instead belong to the same genus as "Ornithocheirus" compressirostris (=Lonchodectes).

 In 2013, Rodrigues and Kellner considered Coloborhynchus to be monotypic, containing only C. clavirostris, and placed most other species in other genera, or declared them nomina dubia.

 Палеонтологи определили птерозавра с самыми крупными зубами.

 К тому же Coloborhynchus capito назван крупнейшим из известных зубастых птерозавров: размах крыльев этого ящера достигал семи метров.

 «Два первых зуба каждой челюсти направлены вперёд и, возможно, были до 7 см длиной, а два зуба за ними — чуть больше 10 см, — рассказывает соавтор работы Дэвид Мартилл из Портсмутского университета (Великобритания). — Вместе они образовывали своего рода розочку, подходящую и для ловли рыбы, и для того, чтобы припугнуть конкурента».

 Дэвид Мартилл и Дэвид Анвин из Лестерского университета (Великобритания) проанализировали фрагментарное ископаемое из коллекции лондонского Музея естественной истории. Его нашли в альбском ярусе нижнемеловой эпохи (около 100 млн лет назад) геологической формации Кембридж-Гринсэнд на востоке Англии. В те времена окрестности Кембриджа находились под водой, но, возможно, на юге Лондона располагался небольшой остров. В этих широтах царил тропический климат. Судя по другим находкам, регион кишел рыбой, ихтиозаврами, плезиозаврами, крокодилами, черепахами, динозаврами (в том числе примитивными птицами).

 Новый птерозавр уступает крупнейшему беззубому собрату под названием Quetzalcoatlus — с его девятиметровым размахом крыльев.

 Результаты исследования будут опубликованы в журнале Cretaceous Research.

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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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 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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 Boreopterus is a genus of pterodactyloid pterosaur from the Barremian-Aptian-age Lower Cretaceous Yixian Formation of Dalian, Liaoning, China.

 The genus was in 2005 named by Lü Jinchang and Ji Qiang. The type species is Boreopterus cuiae. The genus name is derived from Greek boreios, "northern" and pteron, "wing". The specific epithet was chosen to dedicate Cui Xu.

 The genus is based on holotype JZMP-04-07-3, a nearly complete but crushed skeleton and skull. The skull is 235 millimeters long (9.25 inches), low and elongated with a rounded tip. Its wingspan is estimated to have been around 1.45 meters (4.76 feet). Its teeth, especially the anterior nine pairs, are quite large, forming a mesh of sharp teeth at the front of the mouth; the third and fourth teeth from the front are the largest. There are at least 27 teeth in each side of both the upper and lower jaws, which is a large amount.

 Lü and Ji initially placed Boreopterus in the Ornithocheiridae when they described it in 2006, a classification which was supported later that year by David Unwin. However, Lü in 2006 published a cladistic analysis showing Boreopterus to be the sister taxon of Feilongus (together forming the new family, Boreopteridae) in a position more basal than Haopterus.

 In 2013, a more comprehensive study of pterosaur relationships supported the close relationship of Boreopterus and Feilongus, as well as their relatively basal status among pterodactyloids. Andres & Myers (2013) found the "boreopterids" as the sister group of Cycnorhamphus within the archaeopterodactyloid group Gallodactylidae.

 Pterosaurs like Boreopterus are interpreted by Unwin as soaring animals, like today's albatrosses and frigatebirds. However, it has also been suggested that boreopterids foraged while swimming, trapping small prey with their needle-like teeth, a method similar to that of modern Platanista dolphins.

 It has been suggested that the closely related Zhenyuanopterus was merely the adult form of this animal.

 Boreopteridae (meaning "northern wings") is a group of ornithocheiroid pterosaurs from the Aptian-age Lower Cretaceous Yixian Formation of Liaoning, China.

 In 2006, Lu and colleagues named the clade Boreopteridae for the clade containing the common ancestor of Boreopterus and Feilongus and all its descendants, which the authors reclassified as close relatives of the ornithocherids. (Feilongus had originally been considered a gallodactylid). Many possible boreopterids were subsequently described, one possible example being Aetodactylus, which has been claimed to be similar to Boreopterus. Originally considered close relatives of the ornithocheirids, many of these supposed boreopterids have been found to belong to other groups of the pterodactyloid lineage. Boreopterus and Feilongus were found by Andres and colleagues in 2013 to be closely related to Cycnorhamphus, making them members of the Gallodactylidae as had been originally thought when Feilongus was discovered. A subsequent analysis including the other supposed boreopterids found that Boreopterus itself, and therefore the name Boreopteridae, was indeed a member of the ornithocheiroid clade, but that Feilongus was in fact a ctenochasmatoid closely related to Gnathosaurus. According to Andres and colleagues (2014), the true boreopterid clade is limited to Boreopterus, Guidraco, and Zhenyuanopterus.

 The known taxa come from the Yixian Formation of Liaoning, which represented a lake system, suggesting that these animals occurred in freshwater habitats. They are thought to have foraged while swimming, trapping prey with their needle-like teeth; this method of fishing was probably analogous to that of Platanista dolphins, which share a similar dentition.

 Many possible ornithocheirid remains might actually belong to boreopterids, a possible example being Aetodactylus, which has been claimed to be similar to Boreopterus

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 Anhanguera (meaning "old devil") is a genus of pterodactyloid pterosaur known from the Lower-Cretaceous (Aptian age, 112Ma) Santana Formation of Brazil, with referred specimens found in the Upper Chalk Formation and Cambridge Greensand of the UK (up to the late Cenomanian age, 94Ma). This pterosaur is closely related to Ornithocheirus, and belongs in the family Ornithocheiridae within its own subfamily, Anhanguerinae.

 Anhanguera was a fish-eating animal with a wingspan of about 4.5 m (15 ft). Like many other ornithocheirids, Anhanguera had a rounded crests at front of its upper and lower jaws, which were filled with angled, conical but curved teeth of various sizes and orientations. Like many of its relatives, the jaws were tapered in width, but expanded into a broad, spoon-shaped rosette at the tip. It is distinguished from its relatives by subtle differences in the crest and teeth: unlike its close relatives Coloborhynchus and Ornithocheirus, the crest on the upper jaw of Anhanguera did not begin at the tip of the snout, but was set farther back on the skull. Like many ornithocheiroids, (most notably the pteranodonts but also in ornithocheirids such as Ludodactylus) Anhanguera had an additional crest protruding from the back of the skull. However, it was reduced to a small, blunt projection in these animals.

 A study in 2003 showed that Anhanguera held its head at an angle to the ground due to its inner ear structure, which helped the animal detect its balance.

 There are several recognized species of Anhanguera. A. santanae and A. blittersdorfi are known from several fragmentary remains including skulls from the Santana Formation of Brazil. A. cuvieri and A. fittoni, initially described as belonging to the genus Pterodactylus and then Ornithocheirus, are from a slightly later period (Albian) from England, while fragments of pterosaurs that may have affinities with Anhanguera have also been found in Queensland, Australia. The well-known species A. piscator has been redescribed as belonging to the genus Coloborhynchus (Veldmeijer, 2003).

 Anhangueridae is a group of pterosaurs within the suborder Pterodactyloidea. They were among the last pterosaurs to possess teeth. A recent study discussing the group considered the Anhangueridae to be typified by a premaxillary crest and a lateral expansion in the distal rostrum. The same study presented a cladistic analysis, for which an "Agreement subtree" was calculated. The Anhangueridae was found to be sister taxon to the large crested "Tropeognathus".

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 Aetodactylus (meaning "eagle finger") is a genus of ornithocheirid pterodactyloid pterosaur. It is known from a lower jaw discovered in Upper Cretaceous rocks of northeastern Texas, United States. Aetodactylus is only the second ornithocheirid genus to be discovered in North America.

 Aetodactylus is based on SMU 76383 (Shuler Museum of Paleontology, Southern Methodist University), a nearly complete lower jaw lacking the right retroarticular process (the bony prong posterior to the jaw joint), part of the posterior end of the mandibular symphysis (where the two halves of the lower jaw meet), and all but two teeth. This specimen was found in 2006 by Lance Hall near a construction site in Mansfield, near Joe Pool Lake (recorded as SMU Loc. 424). The rock it was found in is a calcareous marine sandstone rich in mud–sized particles, from the middle Cenomanian-age (approximately 97 million years old) Tarrant Formation. Also found were fish teeth and vertebrae, and indeterminate bones. The Tarrant Formation is the lowest rock unit of the Cenomanian–Turonian–age Eagle Ford Group.

 Aetodactylus was named by Timothy S. Myers of SMU in 2010. The type species is A. halli, named in honor of the discoverer. Aetodactylus is differentiated from other ornithocheirids by several anatomical details of the lower jaw, including the slight expansion of the anterior end of the lower jaw, the strong vertical compression of the symphysis, the relatively constant spacing of the teeth, and the slight upward curve of the lower jaw. Myers found that Aetodactylus compared best with the Chinese genus Boreopterus. Aetodactylus represents one of the youngest definitive records of ornithocheirids.

 The jaw SMU 76383 is 38.4 centimetres (15.1 in) long, 15.8 centimetres (6.2 in) (~41%) of which is joined left and right jaws. 27 pairs of teeth were present; the two remaining teeth are pointed, curved slightly backward, flattened from side to side, and slender. The tip of the jaw is slightly expanded (to 1.6 centimetres (0.63 in) from a minimum of 1.3 centimetres (0.51 in) just posterior) and contains the first four pairs of teeth, with the first pair projecting forward. Based on the size of the tooth sockets, the teeth of the second and third pairs were largest, with tooth size decreasing posteriorly. There are small pits between the posterior teeth, interpreted as points where the teeth of the upper jaw rested against the lower jaw. These pits disappear partway along the tooth row, suggesting that the anterior teeth of the upper jaws were longer and projected outwards to a degree. Unlike some other ornithocheirids, such as Anhanguera, Coloborhynchus, and Ornithocheirus, there is no bony crest on the lower jaw.

 It is possible that Aetodactylus might be a boreopterid, as Myers identifies it as being closely related to Boreopterus, and many ornithocheirid remains might belong to boreopterids instead.

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