Some species in the genus Lasioglossum are very small and have metallic colours. In those cases we have to look for specific features. Homalictus females have long hair beneath the abdomen for carrying pollen, and the top of the abdomen is shiny with very little hair. The bee in these images does not meet either criterion. The metallic colour on the thorax is rather dull (well done for spotting it) which is typical of Lasioglossum mundulum.
Thanks Michael, I really appreciate your explanations of the taxonomy. I see on ALA that it’s quite a widespread bee, known from the local area. Interesting that it hasn’t popped up on CNM earlier