Gunneraceae is a family of flowering plants, closely related to Myrothamnaceae, together forming the order Gunnerales. Such a family has been recognized by most taxonomists. Gunneraceae consists of the single genus Gunnera with 63 known species Gunneraceae are known for its species with mammoth-sized leaves, but many species are much smaller and less impressive than the commonly cultivated 'giant rhubarb' Gunnera manicata, which is not related to the edible rhubarb.