Oak Ladybird Scymnus auritus

Also known as Oak Scymnus (e.g. in the Ladybirds field guide by Helen Roy and Peter Brown).

This was swept from Pedunculate Oak. I wasn't confident identifying it base on the information given in the field guide so turned to Andrew Duff's key. The pair of keels on the prosternum weren't easy to see at any angle and at some angles the postcoxal lines on the first visible sternite seemed to be incomplete (but a slight change of angle revealed their true extent clearly). Once those characters had been resolved it seemed to key to auritus but certain elements of the description didn't perfectly match - any ferruginous on the hind margin of the elytra was barely perceivable (it actually shows up better in the photos than it did looking down the microscope) and there was ferruginous on the head but not on the pronotum (the decription suggested it should be on both for male auritus and on neither for female auritus). In view of this I checked the genitalia and the spermatheca (it was a female) matched Duff's diagram for auritus. I measured the beetle to be 2.23mm long.

female Oak Ladybird Scymnus auritus showing elytral hairs, prosternum (2 views), postcoxal line, tip of elytra (2 views), face and spermatheca, Gressenhall museum (Norfolk, UK), 7th July 2024