Creature Feature: White-lined Sphinx Moth

White-lined sphinx moths are common pollinators across the southwest. They're so big, people mistake them for hummingbirds!

In honor of National Moth Week, this month's featured creature is the white-lined sphinx moth—a crowd favorite across the southwest.

These things are big. The caterpillars, also known as hornworms, are juicy chonkers. The chrysalis is the size of your entire thumb. The adult moths, up to three inches across, are often mistaken for hummingbirds when they're out pollinating flowers.

Speaking of pollinating, the white-lined sphinx has a tight relationship with one of San Diego's more mysterious plants, the sacred datura, or jimson weed. The plant is deliriously toxic to mammals (and people), but the caterpillars chow down and the adult moths frequent the datura's enormous white flowers.

Sacred datura is a wild relative of tomatoes, potatoes, peppers, and eggplants (all in the nightshade family). So it's no surprise that our gardens are often ravaged by other members of the sphinx moth family, like the tomato hornworm.

While sphinx caterpillars are a nuisance to many, the adults are a joy to watch as they hover and zoom about in search of nectar. In San Diego, we're lucky to have around twenty different species of sphinx moth, from six-inch stunners to tiny bee mimickers, but the white-lined sphinx is by far the most commonly seen.

For more moths, check your porchlight tonight, and consider joining my next Bug Party After Dark.

Update: In 2024, I felt so inspired by these moths that I created my own sphinx moth costume for Halloween! My ever-so-supportive partner went as a lamp. 😭