Cupido minimus

The story of a female Butterfly laying her eggs.


Picture yourself in a flowering grassland, in Northern Europe. You are a tiny butterfly, Cupido minimus, also called the Small Blue. But if you are indeed small, one of the smallest around, you are in fact rather far from blue. A kind observer would call you bluish brown at most.

But this is hardly the matter of concern at the moment, as you are a freshly mated female. You need to find a site to lay your eggs, all the while avoiding males who could be agressive now that you are mated. What you are looking for is a flowering Kidney vetch, the only food your larvae can eat. You carefully fly around, and here it is! The sweet smell of home, Anthyllis vulneraria. You land on the flower, and stick your abdomen inside to lay one single egg in it.

The next thing to do is to thoroughly rub your butt on the plant, to mark it with your scent. This will ensure that no other female uses this flower as an egglaying site as well. If that were to happen, your caterpillar would eat any other anyway, being there first here. But this is a convenient gesture of politeness, helping everyone. And to the next flower, for the next egg!


Ashe-Jepson, E. et al. (2022) ‘Oviposition behaviour and emergence through time of the small blue butterfly (Cupido minimus) in a nature reserve in Bedfordshire, UK’, Journal of Insect Conservation, 26(1), pp. 43–58. Available at: