There have been some discoveries of unusually well-preserved fossil dinosaur specimens which bear remnants of tissues and bodily structures. Organic tissue was previously thought to decay too quickly to enter the fossil record, unlike more mineralised bones and teeth, however, research now suggests the potential for the long-term preservation of original soft tissues over geological time, leading to the formulation of various hypotheses regarding the underlying mechanisms involved.
Ornithischians
Basal ornithischians
Nickname Catalogue number(s) Institution(s) Taxon Age Unit Country(s) Notes Images INREC K3/109 Institute of Natural Resources, Ecology, and Cryology Kulindadromeus zabaikalicus Bathonian Ukureyskaya Formation Russia A basal ornithischian that preserves protofeathers.
Ornithopods Nickname Catalogue number(s) Institution(s) Taxon Age Unit Country(s) NotesImagesAMNH 5240American Museum of Natural HistoryCorythosaurus casuariusCampanianDinosaur Park FormationAlberta, Canada Trachodon mummy AMNH 5060 American Museum of Natural History Edmontosaurus annectens Maastrichtian Lance Formation United States Duck BillSMF R 4036Naturmuseum SenckenbergEdmontosaurus annectensMaastrichtian Dakota MRF-03 Marmarth Research Foundation Edmontosaurus annectens Maastrichtian Hell Creek Formation United StatesOn display at North Dakota Heritage Center & State Museum Edmontosaurus regalisGasparinisaura cincosaltensis Gryposaurus notabilisMOR 548Museum of the RockiesHypacrosaurus stebingeriLambeosaurus lambeiLambeosaurus magnicristatusMaiasaura peeblesorum Big Paul LACM 17715 Natural History Museum of Los Angeles County Magnapaulia laticaudus Campanian El Gallo Formation Mexico Impression of Big Paul'sskin displayed at LACMParasaurolophus walkeri AMNH 5220, AMNH 5221, and AMNH 5271 American Museum of Natural History Saurolophus osborni Maastrichtian Horseshoe Canyon Formation Canada Various Dinosaurium, among others Saurolophus angustirostris Maastrichtian Nemegt Formation Mongolia, and China Many specimens are known from the locale called the Dragon's Tomb, which often perseveres soft tissues. This makes it a target for fossil poachers Leonardo The Children's Museum of Indianapolis (on ten-year loan from Great Plains Dinosaur Museum and Field Station, 2013-2023) Brachylophosaurus canadensis Campanian Judith River Formation United States Well-preserved mummified specimen WiloThescelosaurus neglectusMaastrichtian Hell Creek Formation South Dakota, United StatesA controversial specimen supposedly with a fossilized four-chambered heart. This is probably a concretionThescelosaurus sp.MaastrichtianHell Creek Formation, Tanis SiteCurrently unpublished hind limb with extensive skin preservation present with scalesNHMUK R2501Natural History Museum, LondonIguanodontia indent.Valanginian Wealden GroupEnglandEndocast with preserved fossilized brain tissue. Possibly belongs to Barilium dawsoni or Hypselospinus fittoni
Ceratopsians Nickname Catalogue number(s) Institution(s) Taxon Age Unit Country(s) Notes ImagesMonoclonius cutleriAMNH FARB 5427Brown, B. A complete skeleton of the horned dinosaur Monoclonius, and description of a second skeleton showing skin impressions. Bull. Am. Mus. Nat. Hist. 37, 298–306 (1917).American Museum of Natural HistoryCentrosaurus apertusTMP 1986.018.0097Royal Tyrrell Museum of PalaeontologyCentrosaurus sp.UALVP 52613, and CMN 2245Canadian Museum of NatureChasmosaurus belli SMF R 4970 Naturmuseum Senckenberg Psittacosaurus sp. Aptian Yixian Formation China This specimen displays pigment preservation, bristles as well as a pigmented cloaca. YFM-R001Ji, S. Initial report of fossil psittacosaurid skin impression from the uppermost Jurassic of Sihetun, northeastern China. Earth Sci. 53, 314–316 (1999).Yanshi Fossil MuseumPsittacosaurus sp.AptianYixian FormationChinaGMC LL2001-01Psittacosauridae indent.AptianYixian FormationChinaAMNH 6418American Museum of Natural HistoryProtoceratops andrewsiCampanianDjodochta Formation, Bayn Dzak LocalityMongoliaUMNH VP 1600Utah Museum of Natural HistoryNasutoceratops titusiCampanianKaiparowits FormationUtah, United StatesLaneHMNS PV.1506, formerly BHI-6273Houston Museum of Natural ScienceTriceratops horridusMaastrichtianLance FormationWyoming, United StatesPreserves extensive skin impressions, including large "nipple" scales on the sacrum and dorsum.CMNFV 56508Canadian Museum of NatureTriceratops prorsusMaastrichtianFrenchman FormationCanadaPreserved skull with impressions of skin on the frill.Triceratops sp.MaastrichtianHell Creek Formation, Tanis SiteNorth Dakota, United StatesCurrently unpublished nearly-complete specimen with skin impressions, possibly killed in the K-Pg extinction event.
Thyreophorans Nickname Catalogue number(s) Institution(s) Taxon Age Unit Country(s) Notes Images Suncor Nodosaur TMP 2011.033. 0001 Royal Tyrrell Museum of Palaeontology Borealopelta markmitchelli Albian Clearwater Formation Canada a nodosaurid which displays pigment preservation, indicating a reddish-brown upper coloration and lighter underside, as well as keratinous sheaths and stomach contents. ML 1347Lourinhã MuseumDeltapodus brodrickiKimmeridgianLourinhã Formation PortugalStegosaurian trackways containing skin impressions.ZDM 0019Xing, Li-da; Peng, Guang-zhao; Shu, Chun-kang (2008). "Stegosaurian skin impressions from the Upper Jurassic Shangshaximiao Formation, Zigong, Sichuan, China: a new observation." Geological Bulletin of China. 27 (7): 1049–1053.Zigong Dinosaur MuseumGigantspinosaurus sichuanensisOxfordianShaximiao FormationChinaA stegosaurian with skin impressions present on the left shoulder on the hindlimbVictoria SMA 0018Aathal Dinosaur MuseumHesperosaurus mjosiKimmeridgianMorrison Formation, Howe QuarryWyoming, United StatesA stegosaurid with skin impressions and remnants of sheaths over the plates QM F1801Queensland MuseumKunbarrasaurus ieversiAlbianAllaru Mudstone FormationAustraliaA basal parankylosaurian with skin impressions and gut contents containing fruits and seedsIVPP V12560Institute of Vertebrate Palaeontology & PaleoanthropologyLiaoningosaurus paradoxusAptianYixian FormationChinaA juvenile ankylosaurid with a large plate on the animal's underside interpreted as a plastron-like bony structure, but is more likely preserved skin.HPM-1206Ji, Q.; Wu, X.; Cheng, Y.; Ten, F.; Ji, Y. (2016). "Fish-hunting ankylosaurs (Dinosauria, Ornithischia) from the Cretaceous of China". Journal of Geology. 40 (2): 183–190. doi:10.3969/j.issn.1674-3636.2016.02.183.Dalian Xinghai Paleontological MuseumLiaoningosaurus paradoxusAptianYixian FormationChinaAnother presumably juvenile specimen found in association with Lycoptera davidi fish fossils, which represent gut contents or were rather deposited below the fossil.NHMUK PV R5161Natural History Museum, LondonScolosaurus cutleriCampanianDinosaur Park Formation CanadaAn ankylosaurid with extensive skin preservation.ZPAL MgD I/113Polish Academy of SciencesTarchia kielanaeMaastrichtian Barun Goyot Formation MongoliaAn ankylosaurid with preserved keratinous scales on the skull.Zuul (originally Sherman) ROM-75860 Royal Ontario Museum Zuul crurivastator Campanian Judith River Formation Montana, United StatesAn ankylosaurid with preserved skin impressions and keratin.
Theropods
Basal theropods Nickname Catalogue number(s) Institution(s) Taxon Age Unit Country(s) Notes ImagesAMNH FR 7224American Museum of Natural HistoryCoelophysis bauriNorianGhost Ranch LocalityNew Mexico, United StatesStomach contents with the bones of what was once believed to belong to a juvenile Coelophysis individual, showing evidence of cannibalism. However, more recent reviews suggest these to be the bones of the small crocodylomorph Hesperosuchus agilisAMNH FR 7223American Museum of Natural HistoryCoelophysis bauriNorianGhost Ranch LocalityNew Mexico, United StatesAnother possible example of cannibalism with a supposed juvenile leg bone in an adult Coelophysis stomach. However, further examination reveals that the juvenile was actually deposited below another individual and was not in the stomach cavity at allSGDS 15-T1St. George Dinosaur Discovery SiteEubrontes giganteusHettangianMoenave FormationUtah, United StatesFoot tracks from a medium sized Dilophosaurus-like theropod with skin impressions Hitchcock SpecimenAC 1/7Gierliński, G. (1996). "Feather-like impressions in a theropod resting trace from the Lower Jurassic of Massachusetts". Museum of Northern Arizona Bulletin. 60: 179–184.Martin, A.J.; Rainforth, E.C. (2004). "A theropod resting trace that is also a locomotion trace: case study of Hitchcock's specimen AC 1/7". Geological Society of America. Abstracts with Programs. 36 (2): 96.Amherst Collage Museum of Natural HistoryFulicopus lyelliiSinemurianPortland FormationMassachusetts, United StatesAn impression of a sitting Dilophosaurus-like theropod that potentially shows impressions of feathers, or may also be a buildup of water in the mud SGDS 642Gatesy, S. M. (2001). Skin impressions of Triassic theropods as records of foot movement. Bulletin of the Museum of Comparative Zoology 156, 137–149.St. George Dinosaur Discovery Site Grallator isp.Norian-Rhaetian Fleming Fjord FormationGreenlandMedium sized coelophysoid theropod trackways featuring scale impressions SGDS 1165St. George Dinosaur Discovery SiteGrallator isp.HettangianMoenave FormationUtah, United StatesShort ridges likely representing folds of skin found in at least one trackwayGrallator variabilisHettangianGrand-Causses FormationFranceTrackways bearing sales impressions Noe, D., Lockley, M. & Hadden, G. (2014). Vertebrate tracks from the Cretaceous Dakota Group, Gunnison Gorge National Conservation Area, Delta County, Colorado. New Mexico Museum of Natural History and Science, Bulletin 62, 385–391.Magnoavipes isp.CenomanianDakota FormationColorado, United StatesTrackways bearing small scale impressions from an averostran of some sortCUE JJ_M01-3Jinju Pterosaur Footprint MuseumMinisauripus chuanzhuensisAlbianHaman FormationSouth KoreaTiny, probably juvenile, theropod track marks with skin impressionsAverostra indent.TuronianKaskapau FormationCanadaSmall scale impressions found in trackways
Avialans