Pterodactylus ( /ˌtɛrəˈdæktɨləs/ from the Greek πτεροδάκτυλος, pterodaktulos, meaning "winged finger" /ˌtɛrəˈdæktɨl/) is a genus of pterosaurs, whose members are popularly known as pterodactyls. It was the first to be named and identified as a flying reptile. Its fossil remains have been found primarily in the Solnhofen limestone of Bavaria, Germany, dated to the late Jurassic Period (early Tithonian), about 150.8-148.5 million years ago, though more fragmentary remains have been identified from elsewhere in Europe and in Africa. It was a carnivore and probably preyed upon fish and other small animals. Like all pterosaurs, the wings of Pterodactylus were formed by a skin and muscle membrane stretching from its elongated fourth finger to its hind limbs. It was supported internally by collagen fibres and externally by keratinous ridges.

 The name derives from the Greek words pteron (πτερόν, meaning 'wing') and daktylos (δάκτυλος, meaning 'finger') and refers to the way in which the wing is supported by one large finger.

 Pterodactylus is known from over 27 fossil specimens, and though most of those are juveniles, many preserve complete skeletons. The discovery of several specimens with well-preserved soft tissue traces has allowed scientists to faithfully reconstruct the life appearance of Pterodactylus. Pterodactylus was a relatively small pterosaur, with an estimated adult wingspan of about 1.5 meters (5 ft) in P. antiquus. Other "species" were once thought to be smaller. However, these smaller specimens have been shown to represent juveniles of Pterodactylus, as well as its contemporary relatives Ctenochasma, Germanodactylus and Gnathosaurus.

 The skulls of adult Pterodactylus were long and narrow with about 90 large, conical teeth. The teeth extended back from the tips of both jaws, and became smaller farther away from the jaw tips (unlike some relatives, where teeth were absent in the upper jaw tip and were relatively uniform in size). The teeth extended farther back into the jaw than in close relatives, as some were present below the front of the nasoantorbital fenestra, the largest opening in the skull. Unlike related species, the skull and jaws were straight, not curved upwards. A small, hooked beak was present in the very tips of the jaws, with both upper and lower hook no larger than the teeth that surrounded them.

 The neck was long, and covered in long, bristle-like pycnofibres. A throat pouch extended from about the middle of the lower jaw to the upper part of the neck.ъ

 Pterodactylus, like related pterosaurs, had a crest on its skull composed mainly of soft tissues. In adult Pterodactylus, this crest extended between the back edge of the antorbital fenestra (the largest opening in the skull) and the back of the skull. The back of the crest extended upward into a backward-curving cone-shaped structure. The crest was composed mainly of long, hardened fibres (twisted together in a spiral pattern inside the conical part of the crest), and covered in scales. In at least one specimen of P. longicollum, the crest had a short bony base, also seen in related pterosaurs like Germanodactylus. Crests have only been found on large, fully adult specimens of Pterodactylus, indicating that this was a display structure and only developed when individuals reached maturity.

 The wings were long, and the wing membranes appear to have lacked the furry covering of pycnofibres present in some other pterosaurs (such as Pterorhynchus and Jeholopterus). The wing membrane extended between the fingers and toes as webbing, and a uropatagium (secondary membrane between the feet and tail) was present, as well as a propatagium (membrane between the wrist and shoulder). Both the finger and toe claws were covered in keratin sheaths that extended and curved into sharp hooks well beyond their bony cores.

 Like other pterosaurs (notably Rhamphorhynchus), Pterodactylus specimens can vary considerably based on age or level of maturity. Both the proportions of the limb bones, size and shape of the skull, and size and number of teeth changed as the animals grew. Historically, this has led to various growth stages (including growth stages of related pterosaurs) being mistaken for new species of Pterodactylus. Several detailed studies using various methods to measure growth curves among known specimens have demonstrated that there is actually only one valid Pterodactylus species, P. antiquus.

 The youngest immature Pterodactylus specimens have a small number of teeth (as few as 15), and the teeth have a relatively broad base. The teeth of older specimens are both narrower and more numerous (up to 90 teeth are present in some specimens).

 Pterodactylus specimens can be divided into two distinct year classes. In the first year class, the skulls are only 15-45mm in length. The second year class is characterized by skulls 55-95mm long, but still immature. These first two size groups were once classified as juveniles and adults of the species P. kochi, until further study showed that even the supposed "adults" were immature. A third year class is represented by specimens of the "traditional" P. antiquus, as well as a few isolated, large specimens once assigned to P. kochi that overlap P. antiquus in size. However, all specimens in this third year class also show sign of immaturity. Fully mature Pterodactylus specimens remain unknown, or may have been mistakenly classified as a different genus.

 The distinct year classes of Pterodactylus antiquus specimens show that this species, like the contemporary Rhamphorhynchus muensteri, likely bred seasonally and grew consistently during its lifetime. A new generation of 1st year class P. antiquus would have been produced seasonally, and reached 2nd-year size by the time the next generation hatched, creating distinct 'clumps' of similarly-sized and aged individuals in the fossil record. The smallest size class probably consisted of individuals that had just begun to fly and were less than one year old. The second year class represents individuals one to two years old, and the rare third year class is composed of specimens over two years old. This growth pattern is similar to modern crocodilians, rather than the rapid growth of modern birds.

 Comparisons between the scleral rings of Pterodactylus antiquus and modern birds and reptiles suggest that it may have been diurnal. This may also indicate niche partitioning with contemporary pterosaurs inferred to be nocturnal, such as Ctenochasma and Rhamphorhynchus.

 Numerous species have been assigned to Pterodactylus in the years since its discovery. In the first half of the nineteenth century any new pterosaur species would be named Pterodactylus, which thus became a typical "waste-basket taxon". Even after clearly different forms had later been given their own generic name, new species would be created from the very productive late Jurassic German sites, often based on only slightly different material.

 Around 1980, subsequent revisions by Peter Wellnhofer had reduced the number of recognized species to about half a dozen. Many species assigned to Pterodactylus had been based on juvenile specimens, and subsequently been recognized as immature individuals of other species or genera. By the 1990s it was understood that this was even true for part of the remaining species. P. elegans, for example, was found by numerous studies to be an immature Ctenochasma. Another species of Pterodactylus based on small, immature specimens is P. micronyx. However, it has been difficult to determine exactly of what genus and species P. micronyx might be the juvenile form. Stéphane Jouve, Christopher Bennett and others suggested that it probably belongs either to Gnathosaurus subulatus or one of the Ctenochasma species, but more data and study would be required to determine which one.

 The only well-known and well-supported species left were P. antiquus and P. kochi. However, most studies since the 1990s have found little reason to separate even these two, and have treated them as synonymous. In 1996, Bennett suggested that the differences between specimens of P. kochi and P. antiquus could be explained by differences in age. In a 2004 paper, Jouve used a different method of analysis and recovered the same result, showing that the "distinctive" features of P. kochi were age-related, and using mathematical comparison to show that the two forms are different growth stages of the same species.

 A special case is P. longicollum, named by von Meyer in 1854, based on a large specimen with a long neck and fewer teeth. Many researchers, including David Unwin, have found P. longicollum to be distinct from P. kochi and P. antiquus. Unwin found P. longicollum to be closer to Germanodactylus and therefore requiring a new genus name. It has sometimes been placed in the genus Diopecephalus because Harry Govier Seeley based this genus partly on the P. longicollum material. However, it was shown by Bennett that the type specimen later designated for Diopecephalus was a fossil belonging to P. kochi, and no longer thought to be separate from Pterodactylus. Diopecephalus is therefore a synonym of Pterodactylus, and as such is unavailable for use as a new genus for "P." longicollum.

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 Размеры тела в сравнении с человеком (серым показаны гипотетические размеры взрослой особи, зелёным - размеры найденных сеголетков):

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 Puntanipterus was a genus of dsungaripterid pterodactyloid pterosaur from the Upper Jurassic-Lower Cretaceous La Cruz Formation of San Luis, Argentina.

 The genus was in 1975 named by José Bonaparte and Teresa Sánchez. The type species is Puntanipterus globosus. The genus name refers to the Puntanos, the colloquial name for the inhabitants of the province of San Luis after the old name of their capital "San Luis de la Punta de los Venados", and combines this with a Latinized Greek pteron, "wing". The specific name means "spherical" in Latin, a reference to the form of the lower tibia.

 It is based on holotype PVL 3869 (earlier FML 3869) found in 1972, a 105 millimetres long tibiotarsus and seven centimetres long fibula; referred to it were a back vertebra and a wing and foot phalanx. The leg bones were described as similar to those of Pterodaustro (from slightly younger rocks), except for having an expanded spherical joint at the ankle and spiny processes on the side faces of the tibia at that end.

 Bonaparte in 1978 classified Puntanipterus as a member of the Pterodaustridae. The same year Peter Wellnhofer was more careful and limited his assessment to a Pterodactyloidea incertae sedis. In 1980 Peter Galton concluded it belonged to the Dsungaripteridae. It was still by many considered to be a dsungaripterid by the time Peter Wellnhofer published The Illustrated Encyclopedia of Pterosaurs (several editions in the 1990s).

 However, in the nineties several tibiae conforming to that of Puntanipterus were found in the same strata as Pterodaustro; a direct comparison is only impossible because more complete specimens of the latter are always very compressed, deforming the ankle morphology; but smaller fragments containing not-compressed ankles all have the build of a Puntanipterus tibiotarsus. This is by South American workers seen as a strong indication that both forms are identical.

 Glut reports a personal communication from Laura Codorniú and Luis Chiappe (2004) that Puntanipterus should be regarded as a junior synonym of Pterodaustro, but it remains to be seen if this will be supported in the future; it was not done in David Unwin's The Pterosaurs: From Deep Time, published in 2006 (he recognized it as a possibly valid species of uncertain relationships).

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 Рамфоринхи (Rhamphorhynchus) — род вымерших рептилий отряда летающих ящеров (птерозавров), живших в юрском периоде (около 170—140 млн лет назад) на территории Европы (Великобритания, Испания и Германия) и Африки (Ангола и Танзания). Впервые описан палеонтологом Мейером (Meyer) в 1847 году. Включает в себя 4 вида.

 Все летающие ящеры (птерозавры) делятся на две группы — длиннохвостых и короткохвостых крылатых ящеров. Наиболее древние — длиннохвостые, рамфоринхи. С греческого это слово переводится как «кривоклювые», хотя, когда смотришь на реконструкцию головы рамфоринха, хочется назвать его, скорее, кривозубым. Очевидно, эти животные питались рыбой — острые длинные изогнутые зубы позволяли хорошо захватывать и удерживать скользкую добычу. Размах крыльев рамфоринха составлял 181 см.

 Крылья рамфоринхов были более узкими, чем у прогрессивных короткохвостых летающих ящеров. Вероятно, рамфоринхи уступали им в маневренности полета. Хвост служил рулем.

 The largest known specimen of Rhamphorhynchus muensteri (catalog number BMNH 37002) measures 1.26 meters (4.1 ft) long with a wingspan of 1.81 m (5.9 ft).

 Traditionally, the large size variation between specimens of Rhamphorhynchus has been taken to represent species variation. However, in a 1995 paper, Bennett argued that these "species" actually represent year-classes of a single species, Rhamphorhynchus muensteri, from flaplings to adults. Following from this interpretation, Bennett found several notable changes that occurred in R. muensteri as the animal aged.

 Juvenile Rhamphorhynchus had relatively short skulls with large eyes, and the toothless beak-like tips of the jaws were shorter in juveniles than adults, with rounded, blunt lower jaw tips eventually becoming slender and pointed as the animals grew. Adult Rhamphorhynchus also developed a strong upward "hook" at the end of the lower jaw. The number of teeth remained constant from juvenile to adult, though the teeth became relatively shorter and stockier as the animals grew, possibly to accommodate larger and more powerful prey. The pelvic and pectoral girdles fused as the animals aged, with full pectoral fusion attained by one year of age.

 The shape of the tail vane also changed across various age classes of Rhamphorhynchus. In juveniles, the vane was shallow relative to the tail and roughly oval, or "lancet-shaped". As growth progressed, the tail vane became diamond-shaped, and finally triangular in the largest individuals.

 The smallest known Rhamphorhynchus specimen has a wingspan of only 290 millimeters; however, it is likely that even such a small individual was capable of flight. Bennett examined two possibilities for hatchlings: that they were altricial, requiring some period of parental care before leaving the nest, or that they were precocial, hatching with sufficient size and ability for flight. If precocious, Bennett suggested that clutches would be small, with only one or two eggs laid per clutch, to compensate for the relatively large size of the hatchings. Bennett did not speculate on which possibility was more likely, though the discovery of a pterosaur embryo (Avgodectes) with strongly ossified bones suggests that pterosaurs in general were precocial, able to fly soon after hatching with minimal parental care. This theory was contested by a histological study of Rhamphorhynchus that showed the initial rapid growth was followed by a prolonged period of slow growth.

 Having determined that Rhamphorhynchus specimens fit into discrete year-classes, Bennett was able to estimate growth rate during one year by comparing the size of one-year-old specimens with two-year-old specimens. He found that the average growth rate during the first year of life for Rhamphorhynchus was 130% to 173%, slightly faster than the growth rate in alligators. Growth likely slowed considerably after sexual maturity, so it would have taken more than three years to attain maximum adult size.

 This growth rate is much slower than the rate seen in large pterodactyloid pterosaurs such as Pteranodon, which attained near-adult size within the first year of life. Additionally, pterodactyloids had determinate growth, meaning that the animals reached a fixed maximum adult size and stopped growing. Previous assumptions of rapid growth rate in rhamphorhynchoids were based on the assumption that they needed to be warm-blooded to sustain active flight. Warm-blooded animals, like modern birds and bats, normally show rapid growth to adult size and determinate growth. Because there is no evidence for either in Rhamphorhynchus, Bennett considered his findings consistent with an ectothermic metabolism, though he recommended more studies needed to be done. Cold-blooded Rhamphorhynchus, Bennett suggested, may have basked in the sun or worked their muscles to accumulate enough energy for bouts of flight, and cooled to ambient temperature when not active to save energy, like modern reptiles.

 Both Koh Ting-Pong and Peter Wellnhofer recognized two distinct groups among adult Rhamphorhynchus muensteri, differentiated by the proportions of the neck, wing, and hind limbs, but particularly in the ratio of skull to humerus length. Both researchers noted that these two groups of specimens were found in roughly a 1:1 ratio, and interpreted them as different sexes. Bennett tested for sexual dimorphism in Rhamphorhynchus by using a statistical analysis, and found that the specimens did indeed group together into small-headed and large-headed sets. However, without any known variation in the actual form of the bones or soft tissue (morphological differences), he found the case for sexual dimorphism inconclusive.

 In 2003, a team of researchers led by Lawrence Witmer studied the brain anatomy of several types of pterosaurs, including Rhamphorhynchus muensteri, using endocasts of the brain they retrieved by performing CAT scans of fossil skulls. Using comparisons to modern animals, they were able to estimate various physical attributes of pterosaurs, including relative head orientation during flight and coordination of the wing membrane muscles. Witmer and his team found that Rhamphorhynchus held its head parallel to the ground due to the orientation of the osseous labyrinth of the inner ear, which helps animals detect balance. In contrast, pterodactyloid pterosaurs such as Anhanguera appear to have normally held their heads at a downward angle, both in flight and while on the ground.

 Comparisons between the scleral rings of Rhamphorhynchus and modern birds and reptiles suggest that it may have been nocturnal, and may have had activity patterns similar to those of modern nocturnal seabirds. This may also indicate niche partitioning with contemporary pterosaurs inferred to be diurnal, such as Scaphognathus and Pterodactylus.

 Several limestone slabs have been discovered in which fossils of Rhamphorhynchus are found in close association with the ganoid fish Aspidorhynchus. In one of these specimens, the jaws of an Aspidorhynchus pass through the wings of the Rhamphorhynchus specimen. The Rhamphorhynchus also has the remains of a small fish, possibly Leptolepides, in its throat. This slab, cataloged as WDC CSG 255, may represent two levels of predation; one by Rhamphorhynchus and one by Aspidorhynchus. In a 2012 description of WDC CSG 255, researchers proposed that the Rhamphorhynchus individual had just caught a Leptolepides while it was flying low over a body of water. As the Leptolepides was travelling down its pharynx, a large Aspidorhynchus would have attacked from below the water, accidentally puncturing the left wing membrane of the Rhamphorhynchus with its sharp rostrum in the process. The teeth in its snout were ensnared in the fibrous tissue of the wing membrane, and as the fish thrashed to release itself the left wing of Rhamphorhynchus was pulled backward into the distorted position seen in the fossil. The encounter resulted in the death of both individuals, most likely because the two animals sank into an anoxic layer in the water body, depriving the fish of oxygen. The two may have been preserved together as the weight of the head of Aspidorhynchus held down the much lighter body of Rhamphorhynchus.

 Рамфоринх, он же Rhamphorynchus, что означает примерно «клювоморд» или «кривоклювый» – один из наиболее известных птерозваров. Эти летающие ящеры обитали на, или вернее – над территорией современной Европы и Африки. Главным отличием этого вида является длинный хвост с ромбовидным окончанием.

 История исследования этого вида начинается в далеком 1825 году, когда некий коллекционер, Георг, граф Мюнстерский, продемонстрировал найденные останки Самуэлю Томасу Зёммерингу. Последний счел, что скелет принадлежит некой древней ископаемой птице. Когда в процессе исследования окаменелостей были обнаружены зубы, граф отослал копию скелета Георгу Августу Гольдфуссу, который опознал в них птерозавра. Если забыть о всей путанице в наименованиях видов в науке того времени, благодаря чему рамфоринх успел побывать и Ornithocephalus Münsteri, и Ornithocephalus longicaudus, и Pterodactylus münsteri, причем, всё это за какие-то 20 лет, то в 1845 году Герман фон Мейер, который считается основателем палеонтологии позвоночных животных в Германии, присвоил виду последнее упомянутое название. В следующем году ученый пришел к выводу, что между короткохвостыми и длиннохвостыми птерозаврами различия столь существенны, что их следует выделить в отдельный подвид. Интересно также то, что те самые, первые найденные, останки были утеряны во время второй мировой. Обычно в таких случаях новые найденные останки (или неотип) обозначаются как тип, но в данном случае от этого отказались, так как существовало большое количество хорошо сохранившихся дубликатов оригинала.

 У молодого рамфоринха был относительно короткий череп с большими глазами. Челюсти имели тупую закругленную кромку. По мере роста животного кромки становились более тонкими и вытянутыми. У взрослых особей также был мощный крюк на нижней челюсти, направленный вверх. Количество зубов с возрастом не менялось; зубы становились более короткими и похожими на пеньки. Вероятно, это помогало ловить более крупную и сильную добычу. В возрасте года происходило объединение грудной клетки с тазовым поясом. Форма хвостовых лопастей также менялась. У юных, «неоперившихся» особей хвостовая лопатка была маленькой, узкой, овальной формы. По мере роста она прогрессировала, хвостовые отростки становились ромбовидными, и, наконец, треугольными у крупных особей.

 Самая маленькая из известных науке особей имела размах крыльев всего 29 сантиметров, однако ученые предполагают, что даже столь небольшие экземпляры были способны на полет. Ученые рассматривали две гипотезы: первая – птенцы с самого рождения обладали размерами и силой, достаточными для полета и вторая – молодым рамфоринхам требовался некоторый период ухода и обучения со стороны родителей. Пока не был исследован эмбрион, содержащий окаменевшие костные останки, не было возможности предположить, какая из гипотез была более правдоподобна, но последние исследования показали, что рамфоринхи были скорее всего выводковыми животными и птенцы уже вскоре после рождения обладали способностью к полёту.

 Позвоночник рамфоринхов состоял из 8 шейных, 10—15 спинных, 4— 10 крестцовых и 10—40 хвостовых позвонков. Грудная клетка была широкой и имела высокий киль. Лопатки были длинными, тазовые кости срослись. 

 Рамфоринхи имели длинные хвосты, длинные узкие крылья и большой череп с многочисленными зубами. Длинные зубы разной величины выгибались вперед. Хвост ящера заканчивался лопастью, служившей рулем. Рамфоринхи имели легкие трубкообразные кости. 

 Первый палец имел вид маленькой кости либо совсем отсутствовал. Второй, третий и четвертый пальцы состояли из двух, реже трех костей и имели когти. Задние конечности были довольно сильно развиты. На их концах имелись острые когти. Чрезвычайно удлиненный внешний пятый палец передних конечностей состоял из четырех суставов.

 Рамфоринхи были мелкими птерозаврами, они могли взлетать с земли. Рамфоринхи селились по берегам водоемов большими колониями. Они питались в основном рыбой. Их клюв полный зубов был идеально приспособлен для захвата скользкой рыбы. Рамфоринхи выработали уникальный способ рыбной ловли, при котором мембраны их крыльев оставались сухими: пролетая над водой, рамфоринхи раскрывали клюв и опускали его под воду. Таким образом, они захватывали все, что попадется и что они могли проглотить.

 Кроме рыбы, рамфоринх мог питаться личинками насекомых, которые жили под корой деревьев. Также рамфоринхи питались яйцами других животных, которые откладывали их в песок на берегу.

 Летающие ящеры жили только в мезозойскую эру, причем их расцвет приходится на позднеюрский период. Их предками являлись, по-видимому, вымершие древние пресмыкающиеся псевдозухии. Длиннохвостые формы появились раньше короткохвостых. В конце юрского периода длиннохвостые птерозавры вымерли.

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Tags: Вымершие рептилии, Юра, авеметатарзалии, архозавроморфы, архозавры, диапсиды, птерозавры, рамфоринхоидеи

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