Please check: https://www.inaturalist.org/flags/650242

The hybrid Anagallis × amoena belongs to the genus Lysimachia, but cannot be transferred to the genus Lysimachia under this name because the South American species Lysimachia amoena already exists. The name Lysimachia × amoena does not officially exist, this name was invented on iNaturalist. To date, there is no valid name for this hybrid taxon in the genus Lysimachia. Someone needs to make a name in Lysimachia for it.

After consulting with Rafaël Govaerts from POWO, I decided to call this hybrid Lysimachia arvensis × loeflingii until there is a paper in which this hybrid is given a proper hybrid name.