All monarchs are butterflies, but not all butterflies are monarchs. Monarchs (Danaus plexippus) emerge from their chrysalis fully formed with a wingspan of about 3.5 to 4 inches, so there are no “baby” monarchs. Other butterflies with similar coloration or patterns may be mistaken for monarchs. I recently heard a story about a gardener who spotted what she believed was a monarch, only to watch it bypass the milkweed and land on a willow tree. This butterfly was actually a viceroy—certainly not a monarch. So how can you tell the difference?
The viceroy (Limenitis archippus), slightly smaller than the monarch at 2.5 to 3 inches wide, is the ultimate mimic of its larger look-alike. The first hint is to what plants females lay their eggs upon, butterflies lay eggs on plants their larvae will eat. Monarch caterpillars exclusively consume milkweed, which can make predators sick and therefore reduces the likelihood of monarchs—and their mimics—being eaten by birds. Viceroys, however, use different host plants, including willow species, cottonwoods, poplar, and aspen. They may also lay eggs on certain fruit trees such as cherry, apple, dogwood, and serviceberry. In addition to their smaller size, viceroys have a distinct black horizontal line across their hindwings, a key field mark visible upon closer inspection.
Another common North American butterfly with orange and black coloring is the red admiral (Vanessa atalanta). Red admirals have a wingspan of 1.75 to 3 inches. The butterfly’s wings upperside is brown-black with white spots near the wing tips and a distinctive orange-red band. The underside features blue and white markings with a pink-red bar, while the hindwings show shades of gray and brown. Red admirals may be found along woodland edges, streams, roadsides, parks, and gardens. Their larvae feed on nettles, while adults consume flower nectar, tree sap, and rotting fruit. They survive mild winters as a chrysalis or adult, but many migrate to southern states. Adults may appear as early as March and as late as November.
North American host plants for red admiral larvae include stinging nettle (Urtica dioica), tall wild nettle (U. gracilis), wood nettle (Laportea canadensis), false nettle (Boehmeria cylindrica), pellitory (Parietaria pennsylvanica), mamaki (Pipturus albidus), and hops vines (Humulus).
A second similar butterfly is the queen the queen butterfly, a North and South American species in the family Nymphalidae, with orange wings, a black border, and small white spots. The queen is primarily a tropical species. In the United States, it is generally confined to the southern portion of the country and is found regularly in peninsular Florida and southern Georgia, as well as southern Texas, California, and other states bordering Mexico. Occasionally, subspecies of the queen appear farther north in Kansas, Colorado, and Utah, and strays may reach the Midwest, including Missouri. The “berenice” subspecies occurs largely in the Southeast, while “strigosus” is found in the Southwest.
Another North American butterfly with coloring similar to the monarch is the American painted lady. The painted lady (Vanessa cardui) and the American lady (Vanessa virginiensis) are two native butterflies that may visit your garden when you plant more native species. Painted lady caterpillars feed on many non-woody native plants, especially thistles (Cirsium spp.) and other members of the Asteraceae (sunflower or aster family). American lady caterpillars feed on pussytoes (Antennaria spp.), sweet everlasting (Pseudognaphalium obtusifolium), and other Asteraceae species.
Both species have wingspans under 2.5 inches, with orange and black coloration and distinctive eye spots. They may be found from April through October in the upper Midwestern states and Canada.
The black swallowtail (Papilio polyxenes) is not likely to be confused with a monarch, but its larvae have similar coloring and are often mistaken for monarch caterpillars by beginners. Both species have yellow and black stripes. However, they can be easily distinguished by their host plants. Monarch caterpillars feed exclusively on milkweed, while black swallowtail caterpillars feed on plants in the carrot family, such as parsley, dill, fennel, carrot tops, and rue.
Commonly known as the eastern black swallowtail or American swallowtail, adult black swallowtails are usually found in open areas such as prairies, fields, meadows, parks, wetlands, and sunny backyards. Females are larger than males, with a wingspan of 3.5 to 4.25 inches. Their wings are black with yellow, blue, orange, and red markings. On the upper surface, two rows of yellow spots line the edges, with a powdery iridescent blue area between them and a red eyespot near the margin of each hindwing. Males typically have larger, brighter yellow spots and less prominent blue, while females have smaller, paler yellow spots but a more vivid blue area—a difference known as sexual dimorphism.
Plants in the carrot family—such as Italian parsley, chervil, curly parsley, carrot tops, and dill—are common sites for females to lay their eggs, a behavior swallowtails have adapted to over time. Native host plant options include golden alexanders.
When I was a child, you could buy butterfly-shaped white chocolate pralines in Germany. I loved eating them back then. Today they would be far too sweet for me.