Fruitadens is a genus of heterodontosaurid dinosaur. The name means "Fruita tooth", in reference to Fruita, Colorado (USA), where its fossils were first found. It is known from partial skulls and skeletons from at least four individuals of differing biological ages, found in Tithonian (Late Jurassic) rocks of the Morrison Formation in Colorado. Fruitadens is the smallest known ornithischian dinosaur, with young adults estimated at 65 to 75 cm (26 to 30 in) in length and 0.5 to 0.75 kg (1.1 to 1.7 lb) in weight. It is interpreted as an omnivore and represents one of the latest-surviving heterodontosaurids.

 Fruitadens is known from fossils recovered under a valid paleontological permit in the 1970s and 1980s by teams led by George Callison, for the Natural History Museum of Los Angeles County (LACM). The discovery area, on lands managed by the Bureau of Land Management, is known as the Fruita Paleontological Area; the specimens were found there in sandstones of the Brushy Basin Member. Roughly equivalent beds have been dated to 150.3 ± 0.3 million years old and 150.2 ± 0.5 million years old, indicating an early Tithonian age.

 The fossils now named Fruitadens were first thought to belong to a fabrosaurid similar to Echinodon, a genus from the Early Cretaceous of England; Fabrosauridae at the time was considered a general group of primitive ornithopods, and Echinodon itself had not yet been reclassified as a heterodontosaurid. Fruitadens, although not formally described for a number of years, was briefly described in several works, usually as a relative of Echinodon or a new species of the genus. Formal description came in January 2010, by Richard Butler and colleagues (though the paper was published online before print in late 2009). The type species is F. haagarorum, in recognition of support provided by Paul Haaga Jr., Heather Haaga, Blythe Haaga, Paul Haaga III, and Catalina Haaga for the Natural History Museum of Los Angeles County.

 Fruitadens is based on LACM 115747, consisting of incomplete jaws, a number of vertebrae, and partial hind limbs, of a nearly fully grown individual. At least three other individuals have been found. LACM 115727 is another nearly fully grown individual, known from vertebrae and hind limb bones. This individual was about the same size as LACM 115747, and was five years old at death. LACM 120478 consists of the upper arm and most of the left leg of a juvenile, in its second year. Finally, LACM 128258 includes partial jaws and vertebrae of another juvenile. The largest individuals are estimated to have been about 65 to 75 cm (26 to 30 in) long and 0.5 to 0.75 kg (1.1 to 1.7 lb) in weight. This makes Fruitadens the smallest known ornithischian and comparable in size to the smallest known dinosaurs, outside of birds. Known material of Echinodon and Tianyulong, related heterodontosaurids, comes from similar-sized individuals, but it is not known how old they were upon death.

 Fruitadens was similar to Heterodontosaurus in anatomy, with relatively short arms and long distal sections of the legs (feet and shins). The lower jaws had an enlarged canine-like tooth, with a corresponding gap in the upper jaw. Unlike Echinodon, there wasn't an enlarged tooth in the upper jaw. Uniquely, a small peg-like tooth was present in front of the canine-like tooth. Replacement teeth were present in the jaws, unlike most other heterodontosaurids. The hind limb bones were hollow, like those of small theropod dinosaurs. Fruitadens seems to have been more closely related to Heterodontosaurus than Echinodon, which was closer in time.

 The four individuals were found in localities at the base of the Morrison Formation's Brushy Basin Member, in crevasse splay sandstones deposited in floodplains. The Fruita localities preserved a contemporaneous fauna including snails, clams, crayfish, various insects (represented by trace fossils), the lungfish Ceratodus, ray–finned fish, the turtle Glyptops, rhynchocephalian reptiles Eilenodon and Opisthias, several genera of lizards, a mesosuchian crocodylomorph, and the mammals Fruitafossor, Glirodon, and Priacodon. Disarticulated dinosaur fossils are common in the area.

 Fruitadens was probably bipedal and cursorial, and is suggested to have been omnivorous. Like Echinodon and Tianyulong, other late-surviving heterodontosaurids, Fruitadens had less specialized jaws than Early Jurassic heterodontosaurids like Heterodontosaurus, and is interpreted as a generalist. A 2012 study of the skull suggested its diet was composed of select plant material and possibly insects or other invertebrates.

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Tags: Вымершие рептилии, Юра, авеметатарзалии, архозавроморфы, архозавры, гетеродонтозавры, диапсиды, динозавроморфы, динозавры, птицетазовые

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 Gargoyleosaurus (meaning "gargoyle lizard") is one of the earliest ankylosaurs known from reasonably complete fossil remains. Its skull measures 29 centimetres (11 in) in length, and its total body length is an estimated 3 to 4 metres (9.8 to 13 ft). It may have weighed as much as 1 tonne (2,200 lb). The holotype was discovered at the Bone Cabin Quarry West locality, in Albany County, Wyoming in exposures of the Upper Jurassic (Kimmeridgian to Tithonian stages) Morrison Formation.

 The type species, G. parkpinorum (originally G. parkpini) was described by Ken Carpenter et al. in 1998. A mounted skeletal reconstruction of Gargoyleosaurus parkpinorum can be seen at the Denver Museum of Nature and Science. Gargoyleosaurus was present in stratigraphic zone 2 of the Morrison Formation.

 The holotype specimen of Gargoyleosaurus parkpinorum was collected by Western Paleontology Labs in 1996 and is currently held in the collections of the Denver Museum of Nature and Science, Denver, Colorado. Besides the holotype, two other partial skeletons are known (although not yet described). The holotype consists of most of the skull and a partial postcranial skeleton. The specimen was originally described as Gargoyleosaurus parkpini by Carpenter, Miles and Cloward in 1998, then renamed G. parkpinorum by Carpenter et al. in 2001, in accordance with ICZN art. 31.1.2A.

 Much of the skull and skeleton has been recovered, and the taxon displays cranial sculpturing, including pronounced deltoid quadratojugal and squamosal bosses. The taxon is further characterized by a narrow rostrum (in dorsal view), the presence of seven conical teeth in each premaxilla, an incomplete osseous nasal septum, a linerarly arranged nasal cavity, the absence of an osseus secondary palate, and, as regards osteoderms, two sets of co-ossified cervical plates and a number of elongate conical spines.

 Vickaryous et al. (2004) place Gargoyleosaurus parkpinorum within the Family Ankylosauridae of the Ankylosauria and are in agreement with most previous phylogenetic hypotheses, which place the genus as the sister group to all other ankylosaurids (i.e., members of the Ankylosauridae). These studies however, only utilized the skull, whereas many of the distinctive features of the family Polacanthidae are in the postcranial skeleton.

 Анкилозавры (Ankylosauria — «согнутый ящер») — инфраотряд наземных динозавров отряда птицетазовых, характерной особенностью которых является костные образования на туловище.

 Передвигались на четырёх конечностях, питались растениями. Тело анкилозавров покрывал панцирь, состоящий из сросшихся костных щитков, шипов или спинных поясов, а на хвосте имелся костный вырост, который использовался для самозащиты. Жили анкилозавры в юрском и раннем меловом периодах на территории современных Европы, Северной Америки и Центральной Азии, в меловом периоде в Австралии и Антарктиде. В России обнаружены в верхнем мелу Амурской области.

 Нодозавриды (Nodosauridae) — семейство динозавров отряда птицетазовых, которые жили в период с позднего юрского и до конца мелового периода на территории современных Северной Америки, Азии, Австралии, Антарктиды и Европы. Семейство выделено в 1890 году Чарльзом Маршем и названо по типовому роду нодозавр (Nodosaurus).

 Одни из первых ископаемые нодозаврид, частичные останки левой лопатки (голотип USNM 8571) и несколько остеодермов (голотипы 8610 USNM, 8611) были отнесены к Scelidosauridae по Гилмор (1919); позднее останки лопатки были отнесены к роду Panoplosaurus (Lehman, 1981). В 2000 году Форд, основаясь на голотипе USNM 8610 поместил род Glyptodontopelta в новое подсемейство "Stegopeltinae" с Aletopelta и Stegopelta. Бернс (2008), в обзоре остеодермов анкилозавров, подтвердил законность Glyptodontopelta. Он поместил ее в семейство Nodosauridae, что делает подсемейство "Stegopeltinae" двусмысленным, из-за неопределенных сходств с Aletopelta.

 Исследования ученых показали, что нодозавриды произошли от общего предка тиреофоров. На сегодняшний день базальным членом данной группы является Antarctopelta, жившая около 74-70 млн лет назад. Однако одним из самых ранних нодозаврид является Sauropelta, жившая около 115 млн лет назад.

 В 2011 году был описан вид Propanoplosaurus marylandicus, который являетсяя единственным нодозавридом из раннего мела в восточной части США и является первым прямым доказательством того, что нодозавриды гнездовались на всем восточном побережье.

 Polacanthinae is a grouping of ankylosaurs, possibly primitive nodosaurids. Polacanthines are late Jurassic to early Cretaceous in age, and Kirkland observed they appeared to become extinct about the same time a land bridge opened between Asia and North America.

 Polacanthines were somewhat more lightly armoured than more advanced ankylosaurids and nodosaurids. Their spikes were made up of thin, compact bone with less reinforcing collagen than in the heavily armoured nodosaurids. The relative fragility of polacanthine armour suggests that it may have been as much for display as defense.

 The family Polacanthidae was named by Wieland in 1911 to refer to a group of ankylosaurs which seemed to him intermediate between the ankylosaurids and nodosaurids. This grouping was ignored by most researchers until the late 1990s, when it was used as a subfamily (Polacanthinae) by Kirkland for a natural group recovered by his 1998 analysis suggesting that Polacanthus, Gastonia, and Mymoorapelta were closely related within the family Ankylosauridae. Kenneth Carpenter resurrected the name Polacanthidae for a similar group which he also found to be closer to ankylosaurids than to nodosaurids. Carpenter became the first to define Polacanthidae as all dinosaurs closer to Gastonia than to either Edmontonia or Euoplocephalus. Most subsequent researchers placed polacanthines as primitive ankylosaurids, though mostly without any rigorous study to demonstrate this idea. The first comprehensive study of 'polacanthid' relationships, published in 2012, found that they are either an unnatural grouping of primitive nodosaurids, or a valid subfamily at the base of Nodosauridae.

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Это преувеличение истинного размера тела животного.

 Размеры тела в сравнении с человеком:

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Tags: Вымершие рептилии, Юра, авеметатарзалии, анкилозавры, архозавроморфы, архозавры, диапсиды, динозавроморфы, динозавры, нодозавры, полакантины, птицетазовые, тиреофоры

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