Open Paleo

Syngonosaurus

Seeley, 1879 sin-GON-oh-SAWR-us Nomen dubium

From Greek 'syngonos' meaning 'congenital' or 'related by birth', combined with Greek 'sauros' meaning 'lizard', likely referring to the fused or closely associated bones in the specimen.

113.2–100.5 million years ago Albian, Early Cretaceous
Early Cretaceous stages

Syngonosaurus is an extinct genus of ornithopod dinosaur from the Early Cretaceous. It was an iguanodontian discovered in the Cambridge Greensand of England and was first described in 1879. The type species, S. macrocercus, was named by Harry Seeley in 1879 and later synonymized with the ankylosaur Acanthopholis; Barrett and Bonsor (2020) redescribed the syntype vertebrae, identified them as an indeterminate iguanodontian and regarded the name as a nomen dubium, as they did Eucercosaurus.

Species

Syngonosaurus macrocercus Seeley, 1879 Nomen dubium

Type species

From Ancient Greek 'makros' meaning 'long' or 'large' and 'kerkos' meaning 'tail', referring to the tail of the animal.

Syntypes
CAMSM B55570, CAMSM B55571, CAMSM B55572, CAMSM B55573, CAMSM B55574, CAMSM B55575, CAMSM B55576, CAMSM B55577, CAMSM B55578, CAMSM B55580, CAMSM B55581, CAMSM B55582, CAMSM B55583, CAMSM B55584, CAMSM B55585, CAMSM B55586 , Sedgwick Museum, University of Cambridge
Material
Series of 18 vertebrae from the neck, back, sacrum and tail.
Horizon
Cambridge Greensand Member, West Melbury Marly Chalk Formation, Albian, Early Cretaceous , 113.2–100.5 million years ago The age of the older beds the specimen was reworked from.
Locality
Cambridgeshire, United Kingdom Barrett and colleagues (2020) record that the Cambridge Greensand's tetrapods are "largely reworked from the underlying Gault Formation (upper Albian)", so the type takes the Albian of the Gault while the member it was found in is Cenomanian.

References

  1. Seeley, H. G. (1879). On the Dinosauria of the Cambridge Greensand. Quarterly Journal of the Geological Society of London 35(1-4): 591-636. Geological Society of London. doi:10.1144/gsl.jgs.1879.035.01-04.42 seeley1879a
  2. Barrett, P. M.; Bonsor, J. A. (2020). A revision of the non-avian dinosaurs 'Eucercosaurus tanyspondylus' and 'Syngonosaurus macrocercus' from the Cambridge Greensand, UK. Cretaceous Research 118: 104638. Elsevier BV. doi:10.1016/j.cretres.2020.104638

    Rejects the ankylosaur referrals of Coombs and Maryańska (1990) and Vickaryous and colleagues (2004); identifies the syntypes as an indeterminate iguanodontian and the name as a nomen dubium.

    barrett2020a
  3. Coombs, W. P. Jr.; Maryańska, T. (1990). Ankylosauria. The Dinosauria (Weishampel, D. B.; Dodson, P.; Osmólska, H., eds.) 456-483. University of California Press, Berkeley.

    Lists Syngonosaurus as a synonym of the ankylosaur Acanthopholis.

    coombs1990a
  4. Vickaryous, M. K.; Maryańska, T.; Weishampel, D. B. (2004). Ankylosauria. The Dinosauria, Second Edition (Weishampel, D. B.; Dodson, P.; Osmólska, H., eds.) 363-392. University of California Press, Berkeley.

    Lists Syngonosaurus macrocercus among ankylosaur nomina dubia.

    vickaryous2004a