Slug with mites

I was amazed walking into the kitchen a few minutes ago when I came across this massive slug, stretched to over 10 cm long on the floor. A Limacus maculatus, it was covered on tiny mites, clustered near the bottom of the slug's body (click the photo to enlarge). Slugs and snails often carry mites of the genus Riccardoella but I have never noticed so many in a slug.

UPDATE. Thank you to Richard Comont and Ryan Clark for pointing me to the right species of mites. I have now amended the post.

A rainbow worm

After a long overwintering period with little activity, BugBlog comes to life thanks to these active earthworms. Using my shoe as a measuring device (cropped out of the photo) and back at home I estimated that is was over 11 cm long. There were several of these worms crossing the path on a wooded patch on the university grounds, under the rain. I usually shy away from identifying worms, but the striking colour of the clitellum - the orange band towards the front of the worms called my attention. I used the Opal Identification guide Their colour, large size and yellow tail tip narrowed down to Blue-grey worm (Octolasion cyaneum), although I think rainbow worm would be more appropriate. The species is found on the topsoil on a range of habitats. This worm had some visible injuries - possibly caused by failed predation attempts by Blackbirds or Carrion Crows.

More information
Earthworm guide. Opal. here.