A set of thorny cactus picture desktop wallpapers is shared with everyone. Wallpaper size: 3840x2160. Cactus is a variant of the prickly prickly pear cactus in the Cactaceae family.Clusters of succulent shrubs, 1.5-3 meters high.The upper branches are broadly obovate, obovate-elliptic or nearly round, green to blue-green, hairless; the spines are yellow, with light brown horizontal stripes, hard; the barbs are upright.