Panticarcinus maylandiensis
Panticarcinus maylandiensis
Common name
Spider Crab
Fossil group
Crustaceans
Order
Decapoda
Family
Epialtidae
Genus
Panticarcinus
Taxonomic status
Accepted
Geological age
Ypresian
Summary
Panticarcinus maylandiensis was a small spider crab from the Essex London Clay. Like modern spider crabs it probably moved deliberately across the seabed rather than relying on speed, feeding on small animals and organic material encountered along the way.
Many living spider crabs decorate themselves with algae, sponge or other material for camouflage. We cannot prove that this particular species did the same, but its membership of the spider-crab group makes that a fascinating possibility when imagining it alive in the warm Eocene sea.
Quick Identification
Look for: a small compact majoid carapace with a distinctive ornamented dorsal surface and spider-crab frontal form; use the Collins & Saward type figures to confirm Species-level identification.
Diagnostic Features
- Carapace small and compact, with majoid proportions.
- Dorsal surface is ornamented and regionally differentiated.
- Frontal construction is consistent with a spider crab rather than a swimming crab.
- Lateral margins and regional pattern form a characteristic Panticarcinus outline.
- Locality is not diagnostic; the carapace character combination must match the type material.
Fossil Details
Typical size
Small, centimetre-scale crab; a reliable population range is not established.
Fossil material
Carapace, Claw / Chela
Preservation
The small carapace is easily chipped and the frontal region may be lost. Abrasion can simplify the surface ornament, making comparison with other majoids more difficult.
Similar Species
Recorded Fossil Sites
London Clay Formation
Thames Group
References
- Collins, J.S.H.; Saward, J. (2006). Three new genera and species of crabs from the Lower Eocene London Clay of Essex, England. Bulletin of the Mizunami Fossil Museum, 33, 67–76 View reference
- 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
Last Reviewed
16 August 2026
Reviewed by
Sam Harris