Foumtizia pattersoni

Foumtizia pattersoni

Cappetta, 1976

Common Name: Catshark

Fossil Group: Sharks & Rays
Order: Carcharhiniformes
Family: Scyliorhinidae
Genus: Foumtizia

Summary

Foumtizia pattersoni was a small extinct catshark that lived in European seas during the Eocene. It is known almost entirely from its small teeth and is a recognised member of the London Clay shark fauna.

Its teeth have a strong pointed central cusp with small side points on either side. Most well developed teeth have two pairs of short side cusplets, although one of the outer cusplets can sometimes be reduced or absent.

One of the best identification features is found along the bottom of the front face of the crown, where short, strong folds form a noticeably uneven or wavy edge that hangs over the root. The remainder of the central cusp is generally much smoother.

The combination of a strong central point, short multiple side points, folded lower crown edge and deeply grooved root makes complete specimens relatively distinctive among the small catshark teeth found in the London Clay.

Geological Age & Range Notes

Early to Middle Eocene, with Foumtizia pattersoni particularly well recorded from Ypresian to early Bartonian deposits. Records extend from the Ypresian through the Lutetian and into the early Bartonian, with possible but uncertain occurrences in the Priabonian of the Late Eocene.

Fossil Material

Tooth

Known Localities

Diagnostic Features

Key features used to recognise and identify this species:

  • Teeth are small, normally only a few millimetres across.
  • The middle of the tooth has a strong, sharply pointed central cusp.
  • The central point is relatively thick at its base and becomes quickly narrower towards the tip.
  • The central cusp can look slightly rounded or swollen rather than completely flat when viewed from the side.
  • There are normally small pointed cusplets on either side of the main point.
  • Well developed teeth typically possess two pairs of short side cusplets.
  • The side points are relatively short and broad at their bases, rather than long needle-like points.
  • On some side teeth, one of the outermost small points can be reduced or completely absent, so the number of visible cusplets can vary.
  • The main surface of the central cusp is generally fairly smooth.
  • Along the bottom of the front face of the crown are several short but strong vertical folds or wrinkles.
  • These folds create a distinctly wavy lower edge to the crown.
  • The bottom of the crown projects out over the root, almost like a small shelf or lip.
  • On some teeth, particularly those from farther around the jaw, these folds can join together and form a more obvious raised ridge along the bottom of the crown.
  • The inside face of the crown is noticeably more rounded and swollen than the outside face.
  • Very fine wavy lines may occur on parts of the inside surface, but these can be extremely faint.
  • The cutting edges are smooth and unserrated.
  • The root is broad and has a fairly flat underside.
  • A deep groove runs through the centre of the root, clearly dividing the central root area.
  • Front teeth tend to have more clearly separated root branches, while teeth from farther around the jaw become broader and more stretched sideways.

Identification Notes

The most useful feature of Foumtizia pattersoni is not simply the central point or the side cusplets. Several Eocene catsharks have teeth with this general appearance.

Instead, concentrate particularly on the bottom edge of the front of the crown.

In F. pattersoni, this area has strong short folds or wrinkles, producing a distinctly uneven, wavy edge which projects forwards over the root. Cappetta considered this combination an important feature of the species when he originally described it from the London Clay.

Quick Identification

Look for:

small catshark tooth + strong pointed central cusp + usually two pairs of short side points + strongly folded wavy lower crown edge + crown overhanging the root + deep groove through the root.

Look at the side points

A good tooth commonly has:

two small points + central cusp + two small points.

The outer pair may be considerably smaller than the inner pair.

However, not every tooth will show all four side points. On some lateral teeth one of the outer cusplets may naturally disappear, while fossil damage can also remove them.

The number of cusplets should therefore not be used as the only identification feature.

Look at the crown surface

Most of the main central point should look relatively smooth.

The strongest decoration is concentrated close to the bottom of the crown, rather than running all the way towards the tip.

This is important because some similar species have much heavier folds covering a greater proportion of the tooth.

Front and side teeth look different

Teeth from near the front of the mouth are generally:

  • taller
  • more upright
  • more compact
  • more symmetrical
  • equipped with more clearly separated root branches

Teeth from around the sides of the jaw become:

  • broader
  • more stretched sideways
  • slightly less symmetrical
  • more strongly folded along the bottom of the crown

This variation means that two teeth from the same species can initially look quite different.

Check the root

A complete root makes identification much easier.

The underside should be relatively flat, with a pronounced central groove.

If the root and side cusplets have both been lost, identification to species becomes considerably less reliable.

Similar Species

References & Literature

Cappetta, H. (1976). Sélaciens nouveaux du London Clay de l’Essex (Yprésien du Bassin de Londres). Geobios, 9(5), 551–575.
The original description of Scyliorhinus pattersoni from the London Clay of Essex.

Ward, D.J. (1980). The distribution of sharks, rays and chimaeroids in the English Palaeogene. Tertiary Research, 3(1), 13–19.
Important reference for the distribution of F. pattersoni through the English Palaeogene succession.

Kemp, D.J. (1982). Fossil sharks, rays and chimaeroids of the English Tertiary period. Gosport Museum.
Useful illustrated reference covering British Palaeogene sharks and rays.

Bor, T.J. (1985). Elasmobranch teeth (Vertebrata, Pisces) from the Dongen Formation (Eocene) in the Netherlands. Mededelingen van de Werkgroep voor Tertiaire en Kwartaire Geologie, 22(2), 73–122.

Malyshkina, T.P. (2006). Late Eocene scyliorhinid sharks from the Trans-Urals, Russia. Acta Palaeontologica Polonica, 51(3), 465–475.
Provides detailed descriptions of Foumtizia tooth morphology and comparisons between F. pattersoni and related species. It also discusses the uncertainty surrounding much younger Russian teeth resembling F. pattersoni.

Rayner, D., Mitchell, T. & Rayner, M. (2009). London Clay Fossils of Kent and Essex. Medway Fossil and Mineral Society.
Useful reference for the London Clay fauna of Kent and Essex.

Iserbyt, A. & De Schutter, P.J. (2012). Quantitative analysis of Elasmobranch assemblages from two successive Ypresian (early Eocene) facies at Marke, western Belgium. Geologica Belgica, 15(3), 146–153.
Documents F. pattersoni within Belgian Ypresian shark assemblages.

Cappetta, H. (2012). Chondrichthyes: Mesozoic and Cenozoic Elasmobranchii: Teeth. Handbook of Paleoichthyology, Volume 3E.
Major modern reference for fossil shark tooth morphology and classification.