If so this is a remarkable insect. It was first described as new to science as recently as 1993, from specimens found in southern Europe. This seems remarkable to me. If it was on a less well documented continent I wouldn't have been surprised but bees are a well studied group the wildlife of Europe is probably the best studied on the planet. Having made it entry it has spread rapidly. First found in the UK in Dorset it has continued to spread and has be found all along the south coast from Kent to Cornwall and in the adjoining counties of Wiltshire, Somerset, Surrey and Essex. It is common on the Channel islands and is rapidly spreading north through Europe. As the name suggests it is dependant on ivy and it has a flight period from September until early November to correspond with the ivy flowering period. It is a solitary bee but the nests can be in large aggregations. They are made is loose sandy soil, often on south facing banks. The BWARS (Bees, Wasps & Ants Recording Society) currently have a mapping project, so if you find one, if possible photograph it and submit the record to them online here
Another insect that I was slightly surprised to find in the garden was this Wall Butterfly. A Long time ago, when I was a kid I was already mad about butterflies and birds. This was one of the common butterflies that we could find around the houses and alleyways of Bexleyheath where I lived. Today, however, is a very different picture, with this species suffering severe declines over the last several decades. It is now confined to primarily-coastal regions and has been lost from many sites in central, eastern and south-east England.