The first tetrapod track recorded from the Rhaetian in the British Isles (2025)

Late Triassic dinosaur tracks from Penarth, south Wales

Geological Magazine

Evidence of Late Triassic large tetrapods from the UK is rare. Here, we describe a track-bearing surface located on the shoreline near Penarth, south Wales, United Kingdom. The total exposed surface is c. 50 m long and c. 2 m wide, and is split into northern and southern sections by a small fault. We interpret these impressions as tracks, rather than abiogenic sedimentary structures, because of the possession of marked displacement rims and their relationship to each other with regularly spaced impressions forming putative trackways. The impressions are large (up to c. 50 cm in length), but poorly preserved, and retain little information about track-maker anatomy. We discuss alternative, plausible, abiotic mechanisms that might have been responsible for the formation of these features, but reject them in favour of these impressions being tetrapod tracks. We propose that the site is an additional occurrence of the ichnotaxon Eosauropus, representing a sauropodomorph trackmaker, there...

Variety and interpretation of dinosaur tracks from the Isle of Wight (Lower Cretaceous, Southern UK)

Introduction Dinosaur tracks and traces have been known from strata on the Isle of Wight (off the south coast of England) since the late 19th Century (Martill and Naish, 2001). Here, early Cretaceous (late Barremian - early Aptian) strata of the Wealden Group are famous for the fossil remains of dinosaurs, including footprints assigned to a number of different taxa. Described traces from the Island include those interpreted as having been left behind by medium-to-large sized ornithopods and small-to-medium sized theropods as well as the possible tracks of sauropods. All of these taxa are known from the Island on the basis of their skeletal remains. Here, we augment the dinosaur tracks known from the Isle-of-Wight by presenting a large collection of footprints all collected by one of us (DD) from the Vectis Formation, exposed on the southern coast of the Island (Radley et al., 1998). Our ongoing work allows, for the first time, a comprehensive review of the dinosaur ichnoassociations known from the Isle-of-Wight. Geological setting Although the precise stratigraphical location of the DD footprint site is not reported here, all the specimens come from Diplocraterion Bed 1 (Radley et al., 1998), within the widespread Vectis Formation. On the island, this formation can be up to 80 metres in thickness (within the Wealden Group of sediments), and comprises (for the most part) a series of mudstone-dominated cycles deposited in coastal lagoonal settings. Sediment viscosity of this type and sedimentary environment is thought ideal for the preservation of footprints (Falkingham et al., 2011). Currently, the best footprint localities on the southern coast of the Isle-of-Wight are exposed only at very long spring tides. Material and methods 10 dinosaur footprints from a much larger recovered sample are noted here, referred to using DD_numbers following the discoverer’s initials. All are preserved as natural casts; according to Radley et al. (1998) and Goldring et al. (2005) footprints were first impressed onto a muddy layer and then infilled later by sand-grade bioclastic sediment packed with the gastropod Viviparus and the rarer bivalve Filosina (Fig. 1). An overlaid tabular layer (seen, for example, in specimens DD 01 and DD 06) is also present and is dominated by convex-up disarticulated Filosina shells. Footprint preservation is generally very poor with few morphological details preserved apart from digits. 10 tracks in the DD collection were photographed by SP in February 2012. Descriptions and measurements were made following the suggestions of Leonardi (1987). These pictures, taken with a Fujifilm S8000fd, 8 million pixel camera, are all of footprint dorsal surfaces and were processed by MB with Agisoft Photoscan Pro (v. 0.8.4). This allowed fair 3D models to be generated, although the lack of angled photos has led to several incomplete-to-voided regions. Resulting models are nevertheless good enough to allow us to generate colour-coded maps of footprint depths (Fig. 2) as well as contour lines using ParaView (v. 3.14). Measurements of tracks were then made directly using meshes generated in Polyworks (v. 10.0) following the procedures applied and tested in Belvedere et al. (2010). Track description and interpretation The ichnological interpretations presented here are based on incomplete 3D models and thus must be considered preliminary. DD_01. This track (Fig. 2, A-B) is longer (16 cm) than wide (11 cm), roughly bell-shaped and with its anterior part larger than the posterior. Three possible digits are present, short and rounded with no claw impressions. The deepest part is located in the middle of the track, but this preservation could be due to recent erosion. The three blunt toes, together with the general shape of the track, allow us to identify this print as a possible Deltapodus (Romano and Whyte, 1995). DD_02. This tridactyl track is roughly as long (13 cm) as wide (11 cm), with short rounded digits and interdigital angles that are symmetrical. Its short blunt digits and symmetrical interdigital angles suggest an ornithopod trackmaker, but preservation prevents a more detailed interpretation. DD_03. This footprint is slightly longer (18 cm) than wide (17 cm), is asymmetrical (II^III < III^IV) and with digit III probably the longest. All digits are slender with tapering terminations; no pads or claw mark impressions are preserved. These morphological features allow us to identify this footprint (with a reasonable degree of certainty) as a theropod track. DD_04. This trace (Fig. 2, C-D) is one of the most ambiguous recovered. At first glance, from the photo (Fig. 2 E), it might be considered to be from a sauropod manus, whereas based on the 3D model (Fig. 2 F) it is possible to see three clear digits, with probable digit I and metatarsal impressions. As in DD_01, the maximum depth of this track is around the middle of the print and is thus probably a result of recent erosion. This print is longer (17 cm) than it is wide (13 cm) and is slightly asymmetrical (II^III < III^IV). No further information is available, but it is identified here as a probable theropod footprint. Tracks from DD_05 to DD_08 present no clear pad impresssions or claw marks and all have similar morphological charactersitics: slender digits with tapering terminations, asymmetric interdigital angles (II^III < III^IV), athough all are slightly different sizes (see Table 1). All these preserved features allow us to identify them as theropod tracks. DD_09. The preservation of this footprint is quite poor and morphological characteristics are barely identifiable. However, two digits are visible while the third is not well preserved. The footprint is slightly longer (22 cm) than wide (19 cm), and almost symmetrical; the digits are blunt and short probably because of erosion. DD_10. As is the case for DD_09, the preservation of this footprint is very poor but it is possible to clearly recognise two rounded digits while a third is only partially preserved (Fig. 2, G-H). This footprint is longer (23 cm) than wide (21 cm) and has slightly asymmetrical intergitial angles. Although a clear identification for DD_09 and DD_10 is not possible, symmetry in the interdigital angles and the short digits allows to suppose an probable ornithopod trackmaker. Although very preliminary and based on few prints, this study increases our baseline knowledge of Isle of Wight dinosaurs and highlights the potential of ichnological analyses which will provide more detailed palaeobiological data in the future. References BELVEDERE, M., MIETTO, P. and ISHIGAKI, S. 2010. A Late Jurassic diverse ichnocoenosis from the siliciclastic Iouaridène Formation (Central High Atlas, Morocco). Geological Quarterly, 54: 367–380. FALKINGHAM, P. L., BATES, K. T., MARGETTS L., and MANNING, P. L. 2011. The 'Goldilocks' effect: preservation bias in vertebrate track assemblages. Journal of the Royal Society: Interface, 8: 1142-1154. GOLDRING, R., POLLARD, J. E. and RADLEY, J. D. 2005. Trace fossils and pseudofossils from the Wealden strata (non-marine Lower Cretaceous) of southern England. Cretaceous Research, 26: 665-685. LEONARDI, G. 1987. Glossary and manual of tetrapod footprint palaeoichnology. Publicação do Departemento Nacional da Produção Mineral Brasil. Brasíli, 117 p. MARTILL, D. M. and NAISH, D. 2001. Dinosaurs of the Isle of Wight. Palaeontological Association, London, 433 p. RADLEY, J. D., BARKER, M. J. and HARDING, I. C. 1998. Palaeoenvironment and taphonomy of dinosaur tracks in the Vectis Formation (Lower Cretaceous) of the Wessex Sub-basin, southern England. Cretaceous Research, 19: 471-487. WHYTE, M. A. and ROMANO, M. 1994. Probable sauropod footprints from the Middle Jurassic of Yorkshire. Gaia, 10: 15-26.

Palaeoenvironment and taphonomy of dinosaur tracks in the Vectis Formation (Lower Cretaceous) of the Wessex Sub-basin, southern England

Cretaceous Research, 2004

Reptilian ichnofossils are documented from three levels within the coastal lagoonal Vectis Formation (Wealden Group, Lower Cretaceous) of the Wessex Sub-basin, southern England (coastal exposures of the Isle of Wight). Footprints attributable toIguanodonoccur in arenaceous, strongly trampled, marginal lagoonal deposits at the base of the formation, indicating relatively intense ornithopod activity. These were rapidly buried by influxes of terrestrial and lagoonal sediment. Poorly-preserved footcasts within the upper part of the Barnes High Sandstone Member are tentatively interpreted as undertracks. In the stratigraphically higher Shepherd's Chine Member, footcasts of a small to medium-sized theropod and a small ornithopod originally constituted two or more trackways and are preserved beneath a distinctive, laterally persistent bioclastic limestone bed, characterised by hypichnialDiplocraterion. These suggest relatively low rates of dinosaurian activity on a low salinity, periodically wetted mudflat. Trackway preservation in this case is due to storm-induced shoreward water movements which generated influxes of distinctive bioclastic lithologies from marginal and offshore lagoonal settings. The rapidly-deposited footprint-fills occasionally contain fully articulated shallow burrowing bivalves.

The Rhaetian vertebrates of Hampstead Farm Quarry, Gloucestershire, U.K

The Rhaetian marine transgression, which occurred across Europe in the latest Triassic, 205.5 Ma, famously deposited one or more bone beds. Attention has generally focused on the basal bone bed alone, but here we explore this bed, and a stratigraphically higher bone bed at the top of the Westbury Formation, and compare the faunas. The Rhaetian at Hampstead Farm Quarry, Chipping Sodbury, Gloucestershire, UK, has produced more than 26,000 identifiable microvertebrate remains, including teeth and scales of chondrichthyan and osteichthyan fishes, as well as vertebrae of sharks, bony fishes, ichthyosaurs, and plesiosaurs. The higher bone bed (‘bed 9’) contains more small specimens than the basal bone bed, and they are also less abraded, suggesting less transport. Both bone beds yield largely the same taxa, but Rhomphaiodon minor and rare Vallisia coppi and Sargodon tomicus are found only in the basal bone bed. Duffinselache is reported only from units above the basal bone bed, but low in the Westbury Formation, and durophagous teeth only from two horizons. Four out of nine chondrichthyan species are common to both bone beds, whereas Rhomphaiodon minor and Ceratodus are absent, and hybodonts in general are rarer, in bed 9. Bed 9 is the richer source of marine reptile remains, including ichthyosaur teeth, jaw fragments, vertebrae, rare plesiosaur teeth and vertebrae, and a few Pachystropheus vertebrae and limb bones. Whereas the basal bone bed represents considerable transport and possible storm bed deposition associated with the onset of the Rhaetian Transgression, bed 9 was deposited under a lower energy regime.

A marine vertebrate fauna from the Late Triassic of Somerset, and a review of British placodonts

Proceedings of the Geologists' Association, 2015

Microvertebrates from the basal Rhaetian Bone Bed (latest Triassic) at Aust Cliff, S.W. England

Proceedings of the Geologists' Association, 2018

A Middle Jurassic dinosaur trackway site from Oxfordshire, UK

Palaeontology, 2004

Tracking Dinosaurs on the Isle of Wight: a review of tracks, sites, and current research

The Wealden exposures on the Isle of Wight have long been noted for their dinosaur footprints and trackways and represent a unique ichnological resource. However, with a few notable exceptions, these ichnites remain largely unstudied and documentation has been sporadic and often concentrated on a few particular sites. Thus, their context within the Lower Cretaceous is poorly understood. The vertebrate ichnological record of the Wessex Sub-basin is currently being re-assessed. We review the main sites containing dinosaur footprints on the Isle of Wight. We also look at previously-known sites, and present new research using techniques such as photogrammetry to accurately record, preserve, and distribute ichnological data, especially data recorded in the dynamic foreshore and cliff environments, where many trace fossils are frequently lost as a result of human activity, weathering, erosion, and changing marine dynamics. Although the ichnoassemblages of the island’s Wealden facies are dominated by ornithopod tracks including Caririchnium and Amblydactylus, we also report the first occurrence of the ankylosaurian track Tetrapodosaurus in both the Wessex and Vectis Formations, alongside the previously reported stegosaurian Deltapodus, as well as the occurrence of tracks left by saurichian tracemakers. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113, 737–757.

Vertebrates from the Late Triassic Thecodontosaurus-bearing rocks of Durdham Down, Clifton (Bristol, UK)

The ecology of a late triassic reptile assemblage from gloucestershire, England

Palaeogeography, Palaeoclimatology, Palaeoecology, 1983