Nematodes of the family Mermithidae were found parasitizing adults and nymphs of the species Hortensia similis (Auchenorryncha: Cicadellidae). The host specimens were collected from weeds associated to citrus orchards located in Corrientes, Argentinean province, during a biodiversity study in 2015. As far as we know, this is the first South American example of leafhoppers parasitized by mermithids.
