Jim Almond has sent in these photos of a female Common Blue Damselfly which illustrate some of the useful diagnostic points to split these from other species. Broad antehumeral stripes are clearly visible on top of the thorax and there’s a notable lack of markings on the side of the thorax. Black ‘rocket shapes’ extend down the abdomen and also visible is the spine on the underside of segment 8 which Jim has enlarged (bottom right). This is absent in other female blue damselflies and is a really useful clue!
