Upper Triassic of South Wales and Central and South-West England

Reptiles of Late Triassic age have been obtained in South Wales and south-west and central England from two main sources: marginal Triassic outcropping in South Glamorgan, where an assemblage of trackways of Norian age has recently been discovered, and from the 'Rhaetic Bone Bed' in the Penarth Group. A third important source of Late Triassic reptiles in Britain is from the cave and fissure fillings in the region of the Severn Estuary: these are treated separately towards the end of this chapter.

The marginal Triassic deposits of South Glamorgan have yielded rare finds of dinosaur footprints from at least two localities. Early finds of isolated dinosaur prints probably came from Scorlon, near Porthcawl. A recent discovery at Bendrick Rock, Barry, comprises numerous trackways assignable to the two dinosaur footprint ichnogenera Anchisauripus tuberosus and Gigandipus.

The 'Rhaetic Bone Bed', actually comprising several ossiferous horizons, is an unusual sequence at the base of the Westbury Beds, with a wide geographic extent. Typical localities yielding reptiles include the following: Devon: Culverhole Point ([SY 275 893]: archosaurs); Somerset: Chilcompton railway cutting ([ST 626 509]; Pachystropheus; Antia, 1979; Duffin, 1980), Hapsford Bridge ([ST 755 490]–[ST 756 489]; prosauropod), Blue Anchor Bay ([ST 042 432]; ?crocodile, Pachystropheus; Richardson, 1911b; Huene, 1935; Sykes, 1977; Storrs and Gower, 1993); Avon: Aust Cliff, Severn Estuary ([ST 566 898]; ichthyosaurs, plesiosaurs, dinosaurs, Pachystropheus; Storrs, 1994), Garden Cliff, Westbury-on-Severn ([SO 718 128]; ichthyosaurs, plesiosaurs, Pachystropheus; Etheridge, 1872; Storrs, 1994), New Clifton, Redland ([ST 585 735]; ?reptile (BMNH)), Carrefour ([ST 585 815]; plesiosaur vertebrae); Glamorgan: Stormy Down ([SS 846 806]; megalosaur dinosaur; Newton, 1899); Leicestershire: Wigston ([SK 603 991]; ?phytosaur; Richardson, 1909), Spinney Hills brickpits ([SP 604 045]; plesiosaur, ichthyosaur; Kent, 1968), Glen Parva brickworks ([SP 56 89]; ichthyosaur, plesiosaur; Browne, 1889, 1894; Fox-Strangways, 1903; Horwood, 1916); Nottinghamshire: Bantycock Pit [SK 811 502] and Staple Pit ([SK 805 499]; dinosaurs, Plateosaurus, Pachystropheus, ichthyosaurs, plesiosaurs, crocodile; Martin and Dawn, 1986), Barnstone (Sykes et al., 1970), Beacon Hill (Johnson, 1950), Stanton-on-the-Wolds [SK 637 312].

A fossil reptile is also known from sediments of 'Rhaetian' age at Wedmore, Somerset ([ST 44 48]; prosauropod Camelotia borealis ['Avalonia', 'Picrodon' ; type specimen: BMNH R2870–4, R2876–8]; Seeley, 1898; Galton, 1985c; Storrs, 1993), and Rhaetian sediments in a large glacial erratic at Linksfield, near Elgin [NJ 223 641] have produced remains of fishes and reptiles, including plesiosaurs (Taylor and Cruickshank, 1993; Storrs, 1994).

Of these numerous localities, only two could be selected as GCR sites, since many of the others are no longer accessible, or offer only marginally different faunas:

1. Bendrick Rock, South Glamorgan [ST 131 668]. Upper Triassic (Norian), Mercia Mudstone Group.

2. Aust Cliff, Avon [ST 565 895]–[ST 572 901]. Upper Triassic ('Rhaetian'), 'Rhaetic Bone Bed', Westbury Formation.

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