Snowberry Clearwing

Hemaris diffinis — the snowberry clearwing — is the BUMBLEBEE-MIMIC sister species to the hummingbird-mimic clearwing (Hemaris thysbe) and one of about 17 species in genus Hemaris (the clearwing hawk moths). The species is widespread across all of North America from southern Canada south through the eastern US to Mexico. Adults are 4-5 cm wingspan with a fat fuzzy body marked by alternating YELLOW AND BLACK BANDS that closely resembles a small bumblebee (Bombus). The species shares the genus Hemaris's identifying CLEAR WING pattern — large central wing patches that are completely TRANSPARENT (the wing scales fall off during the moth's first flight, leaving the bare wing membrane visible), framed by a narrow border of dark scales around the wing margins. The transparent wing patches allow the wings to beat at high frequency without producing visible wing motion, supporting the bumblebee-mimic flight behavior. The species is one of the most successful examples of BUMBLEBEE MIMICRY by a moth. The yellow-and-black body stripes, fuzzy body texture (created by hair-like setae), small size (similar to a bumblebee), and DAY-FLYING behavior (most hawk moths are nocturnal — Hemaris is one of the few day-flying hawk moth groups) make for an exceptionally convincing bumblebee mimic. Observers commonly misidentify snowberry clearwings in flight as bumblebees, especially when the moth is hovering at flowers. The mimicry function is debated: it may provide protection from bird predators (which avoid attacking stinging Hymenoptera), or it may be an example of CONVERGENT EVOLUTION on similar foraging biology (long-proboscis nectar feeding from long-tubed flowers). The genus Hemaris is one of the most-cited examples of multiple mimicry strategies within a closely-related insect genus — Hemaris thysbe mimics a hummingbird (a vertebrate), while Hemaris diffinis mimics a bumblebee (an invertebrate), demonstrating how the same body plan and behavioral toolkit can be channeled into two very different mimicry strategies depending on which model species are abundant in the local environment. Adults feed on nectar from a wide range of long-tubed flowers (especially honeysuckle, snowberry, lilac, and bee balm) using a 2-3 cm extended proboscis. Larvae feed on snowberry, honeysuckle, and dogbane (the source of the common name). The species is harmless to humans and a major beneficial pollinator.