Ctenarytaina fomenae “causes shoot dieback, leaf curl and leaf discoloration, sooty mould growing on the honeydew, which is secreted in large amounts” (Soufo et al. 2018). Their figure 1b illustrates a witches’ broom.

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Particularly remarkable are the two African species C. fomenae and C. melanota which are associated with witches’ broom (Figs 78, 79), probably induced by bacteria such as Phytoplasma which are transmitted by the psyllids.