Lady Beetles (Coccinellidae) are one of the most fascinating families of beetles. In this list I will try to compile all the species that can be found on the territory of Bulgaria.
A lot of data is taken from here - https://www.nmnhs.com/historia-naturalis-bulgarica/pdfs/000098000081997.pdf
Also I've added everything that is listed as "present" in Bulgaria on Fauna Europaea. The list is missing Hyperaspis inexpectata , Hyperaspis minois and Scymnus mesasiaticus.
Some of it might be quite outdated - species that were perhaps present in Bulgaria a long time ago but can no longer be found on this territory.
Also check out this interesting observation of interspecies mating: https://www.inaturalist.org/observations/149831011