Steve Lane & Darren Mann completed "A review of the status of the beetles of Great Britain: The stag beetles, dor beetles, dung beetles, chafers and their allies - Lucanidae, Geotrupidae, Trogidae and Scarabaeidae (NECR224)" in early 2016 and although there are some minor errors and even some possible status changes since the publication in late 2016, it’s the most up-to-date and comprehensive treatment of the Scarabaeoidea available, superseding the status listed in Hyman, P.S. (revised PARSONS, M.S.). 1992. A review of the scarce and threatened Coleoptera of Great Britain. Part 1. UK Nature Conservation: 3. Joint Nature Conservation Committee, Peterborough and Hyman, P.S. (revised PARSONS, M.S.). 1994. A review of the scarce and threatened Coleoptera of Great Britain. Part 2. UK Nature Conservation: 12. Joint Nature Conservation Committee, Peterborough.
This publication is available free to download from http://publications.naturalengland.org.uk/publication/5488450394914816?category=4707656804597760