This year (working on the Plan Bee project for Lancs Wildlife Trust) I found - surprisingly - Andrena tarsata on a fairly isolated / degraded site containing a good number of Tormentil cushions (Potentilla erecta) in Skelmersdale.
Skelmersdale is a new town (1961) though has a relatively large resource of informal public open space / road infrastructure (mostly farm / forest remnants) though acid grassland - and Tormentil more so - is scarce in lowland Lancs as a whole.
I know several surveys / studies have been carried out looking at previous strongholds for this species and N. robertjeotiana and wondered if any observations have been made of visits to other Potentilla sps. As Skelmersdale is a lowland area Trailing Tormentil (P. anglica), Creeping Cinquefoil (P. reptans) and the various hybrids are more likely to occur than P. erecta and I'm keen to try and fund work in surveys / connected habitat works in the area.
I have noticed A. tarsata on Potentilla anglica on one site in the West Pennines (where both tormentil's and putative hybrids occur), though as it has a much larger flower than P. erecta the circular - sideways pollen collecting was more obvious to me there. Most other upland sites only have P. erecta.
I'd be v. grateful for any observations of this sps on other Potentilla's, native or otherwise.