[Palaeontology, Vol. 54, Part 3, 2011, pp. 547–571] NEW INFORMATION ON HAUFFIOSAURUS (REPTILIA, PLESIOSAURIA) BASED ON A NEW SPECIES FROM THE ALUM SHALE MEMBER (LOWER TOARCIAN: LOWER JURASSIC) OF YORKSHIRE, UK by ROGER B. J. BENSON*, HILARY F. KETCHUM , LESLIE F. NOE` ৠand MARCELA GO´ MEZ-PE´ REZ– *Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK; e-mail:
[email protected] Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK; e-mail:
[email protected] àThinktank Birmingham Science Museum, Millennium Point, Curzon Street, Birmingham B4 7XG, UK; e-mail:
[email protected] §College of Life and Environmental Sciences, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK –CASP, West Building, 181A Huntingdon Road, Cambridge CB3 0DH, UK; e-mail:
[email protected] Typescript received 30 March 2010; accepted in revised form 6 July 2010 Abstract: An almost complete, three-dimensionally pre- laterally elongate projections of an undetermined ossification; served plesiosaurian from the Hildoceras bifrons Zone of the and the neural arch contacts the rib facet in all postaxial cer- Alum Shale Member (Whitby Limestone Formation; Lower vical vertebrae. However, the systematic position of Hauffio- Toarcian) of Yorkshire, UK, is described in detail. This repre- saurus, as a pliosauroid or basal plesiosauroid, remains sents a new species of Hauffiosaurus, H. tomistomimus, distin- uncertain. There is little evidence for geographic differentia- guished from H. zanoni (Harpoceras serpentinum Zone, Lower tion of Lower Toarcian plesiosaurian faunas in the United Toarcian, Germany) by the proportionally shorter neck and Kingdom and Germany as minor differences between abun- strongly concave preaxial margin of the tibia.