<unk>  is a species of<unk> , a specialized group of bacteria which lack a cell wall and attack the phloem of plants. This<unk>  causes the diseases ash yellows and lilac witches' broom.
Candidatus Phytoplasma fraxini
Toxoplasma gondii
Mycoplasma incognitus
Mycobacterium orygis
Mycoplasma amphoriforme
Mycoplasma pirum
Mycoplasma orale
Naegleria fowleri