Field Forget-me-not, Field Scorpiongrass, Field Scorpion Grass, Mouse Ear, Rough Forget-me-not: Myosotis arvensis (Synonym: Myosotis scorpioides var. arvensis) - Calyx with spreading or hooked hairs. Corolla small, the limb 1-4 mm wide. Pedicels in fruit generally equal to or longer than the calyx.
Changing Forget-me-not, Yellow and Blue Forget-me-not, Yellow and Blue Scorpion Grass, Yellow and Blue Scorpiongrass, Yellow Scorpiongrass: Myosotis discolor (Synonym: Myosotis versicolor) - Calyx with spreading or hooked hairs. Corolla small, the limb 1-4 mm wide. Pedicels in fruit generally much shorter than the calyx. Plants only flower on the upper half of the plant, the flowers generally not subtended by leaves or bracts. The style is noticeably longer than the nutlets.
African Forget-me-not, Broad-leaf Forget-me-not, Broad-leaved Forget-me-not: Myosotis latifolia - Naturalized.
Bay Forget-me-not, Small Forget-me-not, Small-flowered Forget-me-not, Smaller Forget-me-not: Myosotis laxa - Calyx with closely appressed, straight hairs. Corolla limb 2-5 mm wide. Stems not forming stolons, rather lax an spreading.
Blue Scorpion Grass, Blue Scorpiongrass, Mouse Ear, Strict Forget-me-not: Myosotis micrantha (Synonym: Myosotis stricta) - Calyx with spreading or hooked hairs. Corolla small, the limb 1-4 mm wide. Pedicels in fruit generally much shorter than the calyx. Plants flower from near the base upward with the lower flowers subtended by leaves. Style much shorter than the nutlets.
Early Forget-me-not: Myosotis ramosissima - Introduced from Europe and the Mediterranean region.
Common Forget-me-not, True Forget-me-not, Water Forget-me-not, Water Scorpion Grass: Myosotis scorpioides (Synonym: Myosotis palustris) - Calyx with closely appressed, straight hairs. Corolla limb 5-10 mm wide. Stem often creeping or forming stolons.
Woodland Forget-me-not, Wood Forget-me-not, Woods Forget-me-not: Myosotis sylvatica - Calyx with spreading or hooked hairs. Corolla limb showy, the limb 4-8 mm wide.
Spring Forget-me-not: Myosotis verna (Synonyms: Myosotis macrosperma, Myosotis verna var. macrosperma, Myosotis virginica) -