All thornmints are aromatic annual wildflowers with erect stems and petioled leaves. Inflorescences of thornmints are head-like, in clusters and terminal in form. In the Acanthominthagenus leaf veins are conspicuous and the leaf margins are always spiny, leading to the common name. The characteristics of the genus flower are with a two-lipped calyx and lobes spine-tipped, re-inforcing the basis of the common name. All Acanthomintha have the upper three lobes of its calyx acuminate and the lower two lobes oblong in shape. Acanthominthacorollae are funnel shaped, always white, but sometimes with a tinging of rose or lavender color. The corolla throat is cream colored and its upper lip is hooded, while the longer lower lip is reflexed and three-lobed. All Acanthomintha have four stamens, with the upper two reduced, whether they are sterile or not. Thornmint styles are slender and their fruit is ovoid in shape with smooth exterior texture.