Squalus minor

Squalus minor

(Leriche, 1902)

Common name Dogfish Shark
Fossil group Sharks & Rays
Order Squaliformes
Family Squalidae
Genus Squalus
Taxonomic status Accepted
Geological age Thanetian and Ypresian

Summary

Squalus minor was a small dogfish shark related to living spurdogs. Dogfishes are active predators that can occupy shelf and deeper-water environments and commonly feed on fishes, cephalopods and crustaceans.

Its low overlapping teeth formed a continuous cutting edge rather than a set of tall spearing teeth. This arrangement was suited to gripping and slicing small prey and would have allowed the shark to process food efficiently despite its relatively modest size.

The species is known mainly from isolated teeth, so its preferred depth and detailed behaviour cannot be established. It nevertheless shows that squaliform dogfishes formed part of the varied Palaeogene shark community represented by the London Clay.

Quick Identification

Look for: a tiny, low tooth with the main point leaning strongly sideways rather than straight upwards. Behind it is a smooth rounded shoulder rather than another sharp point. The base is short, broad and fairly flat.

Diagnostic Features

  • Main cusp is low, blade-like and strongly inclined towards one side.
  • Distal heel is broad and rounded rather than forming a separate sharp lateral cusplet.
  • Cutting edges are smooth and unserrated in typical Squalus minor teeth.
  • Labial crown bears a prominent V- or tongue-shaped apron projecting down over the root.
  • Root is low and flattened, without the long paired lobes found in sand-tiger-type sharks.

Fossil Details

Typical size
Teeth are small, usually only a few millimetres wide; dimensions vary with jaw position.
Fossil material
Tooth
Preservation
The low blade-like cusp and distal edge are vulnerable to rolling and edge loss. Worn teeth can become difficult to distinguish from other small squaloids.

Similar Species

Recorded Fossil Sites

Reculver Sand Member

Thanet Formation
Confirmed
Reculver

References

  • 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
Last Reviewed
12 August 2026 Reviewed by Sam Harris