Scraptiidae (false flower beetles)
I started off using Mike Hackston's keys to identify these but in May 2020 I purchased Brian Levey's "British Scrptiidae", one of the RES Handbooks. This is pretty clear and inexpensive so I recommend it, especially if the relevant volume of Duff is out of reach. I've mainly used Levey to identify this family from 2020 onwards, though sometimes turn to Duff or Hackston for added confidence. Even with all three resources some can be really troublesome and I am no longer confident about some of my earlier IDs - resulting in the removal of three species from my records. I have found that some individuals do not conform to the antennal characters given in the keys (for example a frontalis with clearly elongate antennomeres 9 & 10) and I've had to leave some individuals unidentified.
Anaspis regimbarti
Anaspis garneysi
Anaspis frontalis
Anaspis maculata