Trachysoma scabrum

Trachysoma scabrum

Bell, 1858

Common name Glypheid Lobster
Fossil group Crustaceans
Order Decapoda
Family Glypheidae
Genus Trachysoma
Taxonomic status Accepted
Geological age Ypresian

Representative Specimens

Selected reference specimens illustrating this species from different geological units and fossil sites.

Identification Examples

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Summary

Trachysoma scabrum was a glypheid lobster, part of an ancient lobster lineage with a history stretching far back into the Mesozoic. It had an elongated body and a rough, strongly sculptured carapace and would have walked across the seabed searching for food.

Like other large benthic lobsters it was probably an opportunistic predator and scavenger. Its survival into the Eocene London Clay sea is especially interesting because glypheids represent a very old branch of lobster evolution, linking this fauna with much earlier marine ecosystems.

Quick Identification

Look for: an elongate lobster carapace with a conspicuously rough, strongly sculptured surface and glypheid groove pattern; distinguish it from smoother palinurid and nephropid London Clay lobsters.

Diagnostic Features

  • Carapace elongate and lobster-like.
  • Dorsal surface strongly sculptured, giving a rough or scabrous appearance.
  • Regional grooves are prominent and organise the carapace surface.
  • Overall construction differs from both clawed nephropids and palinurid spiny lobsters.
  • The historical combination Glyphea scabra refers to this species and should not be created separately.

Fossil Details

Typical size
Centimetre-scale lobster carapace; reliable whole-body range is not established.
Fossil material
Carapace, Crustacean Appendage
Preservation
Surface sculpture can be reduced by abrasion or pyrite weathering. Carapaces may split along grooves, so incomplete material can lose the distinctive rough appearance.

Similar Species

Recorded Fossil Sites

Synonyms & Previous Names

Glyphea scabra

References

  • J. S. H. Collins; C. J. T. Mellish; A. J. Ross; P. R. Crabb; S. K. Donovan. (2020). A guide to the fossil Decapoda (Crustacea: Axiidea, Anomura, Brachyura) of the British Isles. Proceedings of the Geologists' Association, 131(1), 19–50 View reference
  • Thomas Bell. (1857). A monograph of the fossil malacostracous Crustacea of Great Britain. Part I. Crustacea of the London Clay. Monograph of the Palaeontographical Society, 10, i–viii, 1–44. Palaeontographical Society, London View reference
  • W. J. Quayle. (1987). English Eocene Crustacea (lobsters and stomatopod). Palaeontology, 30(3), 581–612 View reference
Last Reviewed
20 August 2026 Reviewed by Tom Wells