Portunites incerta (Bell, 1857)

Portunites incerta is one of the most common species of crab being found at almost every division and site across the London Clay. The current list for the sites it has been found at include: 

Butts Cliff, Allhallows, Aveley, Maylandsea, Sheppey, Steeple Bay, Tankerton, Seasalter, Herne Bay, Medway Estuary, Hampton Pier, Upnor and Elmley

Acknowledgments:

Thank you very much Tony Mitchell for allowing usage of an image on this page. 

References:

https://www.mindat.org/taxon-4644441.html 

https://www.mindat.org/taxon-4644442.html 

https://www.marinespecies.org/aphia.php?p=taxdetails&id=1619314 

https://commons.wikimedia.org/wiki/Category:Parathranites_tuberogranosus#/media/File:Parathranites_tuberogranosus_(MNHN-IU-2008-12551)_002.jpeg 

https://en.wikipedia.org/wiki/Portunoidea 

Further reading:

http://www.sheppeyfossils.com/pages/Portunites_incerta.htm 

http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=224580 

https://www.dmap.co.uk/fossils/london/other/lonother.htm