Macroplata Swinton, 1930
Macroplata has a unique feature of the pectoral girdle, a distinct notch in the posterior border of the coracoids. The number of rib facets varies along the cervical vertebral column (27 in total), there is only one in the anterior vertebrae but two in the posterior ones. There are 5 pectorals, 19 dorsals, 4 sacrals and 30 caudals.
White (1940) referred the species Plesiosaurus longirostris to Macroplata, and has been confused as the holoype by some authors. M. tenuiceps is the only valid species of Macroplata (Ketchum and Smith, 2010). Benson et al. (2011) referred material pertaining to 'M. longirostris' to Hauffiosaurus under the new combination Hauffiosaurus longirostris.
M. tenuiceps Swinton, 1930
Type material: BMNH R5488, an almost complete skeleton with the distal parts of the limbs missing.
Age and Location
Schlotheimia angulata Zone, Hettangian, Lower Lias, Lower Jurassic, Harbury, Warwickshire, UK.