Six-spotted Spider Beetle (Ptinus sexpunctatus) found in Formby

male Osmia bicornis guarding a mortor hole. (Trevor Davenport)

On April 15th, 2020, I noticed and photographed a male Red Mason Bee (Osmia bicornis) guarding two old “rawlplug” holes in an east-facing wall of my garden in Formby (SD28380802). A week later, a pair was in cop. by the holes. Thereafter, the female busily attended the nest-holes but was elusive and difficult to photograph. Both holes were sealed on April 30th, and the progeny will, hopefully, appear next year.

In the early morning of April 23rd, I noticed a small beetle on the edge of one of the holes which was identified as Ptinus sexpunctatus (Six-spotted Spider Beetle). The following morning, three of them were near the holes

Osmia bicornis pair (Trevor Davenport)

According to NBN Atlas, this is the third v.c.59 sighting, all of which are within the past 5 years. There two records on the NBN Atlas are just to south at Runcorn (2016) and Penketh (2018). There is also a record from 2019 at Woolton by Steve McWilliam. Further East there are a few Yorkshire records going a bit further north. The beetle has a mainly southern distribution but is evidently moving north.

Ptinus sexpunctatus is a scavenger of dead insects and is found near, or in, bee nests; it’s larvae have a commensal relationship with Osmia and Megachile solitary bee genera

Ptinus sexpunctatus (Trevor Davenport)