Horsetail
Guides
Grypus equiseti
horsetail weevil
Grypus equiseti is a weevil species native to Europe that feeds exclusively on horsetail plants (Equisetum spp.). It has been introduced to New Zealand as a biological control agent targeting field horsetail (Equisetum arvense), an invasive weed in that country. The species is notable for its specialized diet and documented success in classical biological control programs.