Sylvestrilamia teretidens

Sylvestrilamia teretidens

(White, 1931)

Common name Sand tiger shark
Fossil group Sharks & Rays
Order Lamniformes
Family Odontaspididae
Genus Sylvestrilamia
Taxonomic status Accepted
Geological age Thanetian and Ypresian

Summary

Sylvestrilamia teretidens was a relatively small sand-tiger-type lamniform shark with slender piercing teeth. It belonged to a widespread Palaeogene community of sharks adapted to catching mobile prey in coastal and shelf seas.

Its narrow teeth were designed primarily for grasping. Small fishes were probably important prey, while cephalopods and other soft-bodied marine animals are also plausible. The dentition suggests a predator that captured prey whole or with limited cutting rather than one specialised for breaking shells or removing large pieces of flesh.

The species is known largely from isolated teeth, leaving its external appearance uncertain. Those teeth nevertheless record a specialised small-to-medium predator forming part of the diverse lamniform fauna of the early Eocene.

Quick Identification

Look for: a small slender sand-tiger tooth with faint vertical striae near the base of the lingual crown face and small, relatively blunt lateral cusplets; compare with more strongly striated Striatolamia.

Diagnostic Features

  • Principal cusp is small to medium, narrow and smooth edged.
  • Faint longitudinal folds commonly occur near the base of the lingual crown face.
  • Lateral teeth carry small, relatively blunt lateral cusplets.
  • Lateral crowns are narrower than in the robust Hypotodus-type morphologies.
  • Root is bilobed with the standard odontaspidid central nutritive division.

Fossil Details

Typical size
Small teeth; a published complete lateral tooth is about 10 mm high, with dimensions varying by jaw position.
Fossil material
Tooth
Preservation
The faint basal striae are easily polished away and the blunt lateral cusplets may be lost. Worn specimens can overlap with other odontaspidids and should be left at family or genus level when the basal crown is missing.

Similar Species

Recorded Fossil Sites

Reculver Sand Member

Thanet Formation
Confirmed
Reculver

Synonyms & Previous Names

Synodontaspis teretidens; Odontaspis teretidens

References

  • Cappetta, H.; Nolf, D. (2005). Révision de quelques Odontaspididae (Neoselachii: Lamniformes) du Paléocène et de l’Eocène du Bassin de la Mer du Nord. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, Science de la Terre, 75, 237–266 View reference
  • Cooper, J. (1977). The palaeontology of the London Clay (Lower Eocene) of the Herne Bay coastal section, Kent, England. Proceedings of the Geologists' Association, 88(3), 163–178 View reference
  • Dineley, D. & Metcalf, S. (1999). Fossil Fishes of Great Britain. Geological Conservation Review Series, 675 pp.. Joint Nature Conservation Committee, Peterborough View reference
  • Rayner, D.; Mitchell, T.; Rayner, M. (2009). London Clay Fossils of Kent and Essex. 228 pp.. Medway Fossil and Mineral Society, Rochester, Kent View reference
  • Ward, D.J. (1978). The Lower London Tertiary (Palaeocene) succession of Herne Bay, Kent. Report of the Institute of Geological Sciences. Institute of Geological Sciences View reference
  • Ward, D.J. (1980). The distribution of sharks, rays and chimaeroids in the English Palaeogene. Tertiary Research, 3(1), 13–19 View reference
  • White, E.I. (1931). The vertebrate faunas of the English Eocene. I. From the Thanet Sands to the Basement Bed of the London Clay. 121 pp.. British Museum (Natural History), London View reference
Last Reviewed
16 August 2026 Reviewed by Sam Harris