Butterflies come in a dazzling array of colors and patterns. While many people are familiar with butterflies that have bright, eye-catching wings, there are also species with dark-colored wings, including some that are solid black. So what are these dark beauties called? The answer depends on the specific species.
Black Swallowtail
One of the most common black butterflies in many parts of North America is the black swallowtail (Papilio polyxenes). As the name suggests, the wings of the black swallowtail are solid black or very dark brown. The males have a distinctive row of yellow spots along the trailing edge of the rear wings, while females have a row of blue spots and more extensive blue markings along the outer margins of the wings.
Black swallowtails are large butterflies, with a wingspan up to 4 inches. They are members of the swallowtail family, Papilionidae, which includes other familiar species like the tiger swallowtail and the spicebush swallowtail. Like their relatives, black swallowtails have tails extending from the hindwings which help confuse predators.
Pipevine Swallowtail
Closely related to the black swallowtail is the pipevine swallowtail (Battus philenor). As the name suggests, the pipevine swallowtail is also solid black with a similar wingspan of 3-4 inches. However, the pipevine swallowtail lacks the distinctive yellow spots of the black swallowtail. It occurs in the southern and southeastern United States, where it feeds on plants in the genus Aristolochia as a caterpillar.
The pipevine swallowtail mimics the poisonous pipeline swallowtail (Battus philenor) which feeds on toxic pipevines as a caterpillar. By resembling the unpalatable pipeline swallowtail, the relatively harmless pipevine evades predation through Batesian mimicry.
Western Ironclad
Out west in the Rocky Mountains and Sierra Nevada is found the western ironclad (Lasaia sula). Also known as the zarucco duskywing, this all-black butterfly has a wingspan around 2 inches. The dark coloration helps it absorb heat in the cooler mountain habitats. Males have lighter brown undersides to the wings.
The western ironclad belongs to the family Hesperiidae, the skippers. It lays its eggs on currant and gooseberry plants. The caterpillars fold and tie the leaves together with silk to form a protected shelter.
Bronze Copper
The bronze copper (Paralucia spinifera) lives up to its name with wings colored a dark bronze-black above. It is found along the coast of southeastern Australia and Tasmania. Growing up to 2 inches across, its wings are edged with orange spots. The undersides are brown with bright green patches.
The bronze copper is a member of the family Lycaenidae. The caterpillars feed on the larvae of the coastal brown ant. The ants protect the caterpillar within their nest while it feeds on ant larvae.
Other Black Species
In addition to these species, various other butterflies around the world are primarily black or nearly black in color, including:
- Crows and nomads (Nymphalidae) – Found in the mountains of Central Asia, these butterflies have black wings with small white spots on the margins.
- Black hairstreak (Satyrium pruinosa) – A small black butterfly found in woodlands of eastern North America.
- Blackveins (Athyma nefte) – Large brushfooted butterflies of southeast Asia with black wings marked with pale veins.
- Batwing (Phocides pigmalion) – A Central and South American skipper with deep black wings and an orange-red body.
Melanism
The black coloration seen in many of these species is a result of melanism. Melanism is an increased amount of black pigment, or melanin, in the wings. It may serve several functions:
- Camouflage – Black wings blend into dark surroundings, helping the butterflies avoid predation.
- Thermoregulation – Dark wings may help absorb solar radiation to raise body temperature.
- Mimicry – Black butterflies may mimic distasteful or poisonous species.
The amount of black pigment can vary considerably within a species based on climate and other factors. Some butterflies display seasonal polyphenism, where melanic forms are more common during cooler parts of the year.
Identifying Black Butterflies
Identifying an all-black butterfly species can be tricky. Looking for small differences in wing shape and patterns is important. Note the shape of the forewings and hindwings and any spots, bands, or other markings visible on the wings or body. Also pay attention to behavior, flight style, and habitat. Photographing the butterfly from multiple angles can help capture diagnostic features. Having a field guide or consulting an expert are also useful for confirming the species.
Conclusion
While black butterflies may seem unassuming compared to their more colorful relatives, they exhibit some fascinating adaptations. Their dark wings allow them to stay warm in cool climates, avoid predation, and communicate with other butterflies. With over 1600 butterfly species in the United States and Canada alone, black butterflies add striking beauty and diversity to backyards and wild areas where they are found.
| Butterfly Name | Location | Wingspan | Distinguishing Features |
|---|---|---|---|
| Black Swallowtail | North America | Up to 4 inches | Solid black wings, yellow spots on males |
| Pipevine Swallowtail | Southeastern U.S. | 3-4 inches | All black with no spots |
| Western Ironclad | Western North America | About 2 inches | Small all black butterfly of the skipper family |
| Bronze Copper | Australia | Up to 2 inches | Dark bronze wings with orange spots |