A tiny black bee with a distinct yellow mark on the back of its neck / front of thorax. (1, 2, 3 & 4). Photo 3 shows the clear, black-veined wings, and thorax, whilst photo 4 shows the thorax in profile, which looks like it has a ‘lifted plate’ on its back. Photo 5 indicates size, and the ‘inverse tear-drop-shaped’ eyes; (very full) pollen baskets are visible in all. The plant the bees were working was Bitter Melon (Momordica charantia). This could be the same Sp as at sighting 4664734 & 4664742.