I headed back to the DWT Villa on Brownsea for a lunch break on my usual volunteering Weds. It was a sunny day, so I took the cuppa I had just made out into the Villa courtyard to have my lunch. This was quickly disturbed by a small, slim black and yellow Bee or Wasp looking around holes in the open back gate. It was obviously not a German Wasp as it was thinner and the markings were wrong. I started thinking about it being one of the Nomad Bees and I took a few quick photos. It disappeared, but returned to look again at the same hole a few minutes later. This gave me the chance for a few more photos, before it flew off again. I gave it another five minutes, while I finished my cuppa and lunch, but it didn't reappear. I was scheduled to take over manning the vid-scope in the Avocet hide and I didn't have the time to hang around to get some better photos. When I got home, I put one of the photos into Google Lens and it suggested one of the Ancistrocerus Mason Wasps. I've not got any books on Wasps and so I forwarded the photos to my mate Steve Morrison, who knows his Wasps.
The feedback from Steve was "the photos are good. I would normally need to have it under the 10x loupe, but the size of the Wasp, the pattern of the first tergite, along with the facial pattern in the last photo all looks good for Ancistrocerus parietinus (Wall Mason Wasp) and I'd accept it such. It's also a female with six exposed abdominal segments as opposed to seven in the male and twelve antennal segments as opposed to thirteen. It's fairly common, but overlooked as all Solitary Wasps are these days".
When I went to add the record to my Birding and Wildlife database, I found I had already seen it once before in my house. I photographed one that was flying into through my open conservatory door and was investigating a small hole in the kitchen door frame, which would have been on the outside of the house before the conservatory was added. Here is a photo of that individual taken in Jun 24, which Steve kindly identified for me. More photos of that individual can be found in this Blog Post of my Wall Mason Wasp.
Looking it up on the BWARS website, it looks to be a relatively widespread species in England & Wales up to Yorkshire, with less frequent records in the far North of England & Scotland. June & July are most likely flying months with less frequent sightings in May & August. The BWARS website states it is a tube-dweller and often nests in the stems of bramble and elder. The Flowers visited are Sea-holly, Bramble, Hogweed and Thistles.