This enchanting creature, photographed by Daniel Pepper in Seattle, is a large and gentle solitary wasp, Sphex ichneumoneus. Commonly known as the great golden digger wasp, it is distributed throughout North America. One of its most striking features is the dual-colored abdomen—black and orange—and the bright orange legs. These wasps are also big. The males average about 19–20 mm long, and the females are a bit bigger at 23–24 mm.
More hairy than most
The great golden digger is hairier than most wasps, sporting a golden fringe on its head and thorax. Wasp hairs and bee hairs differ, and if you were to look under the microscope, you would see that wasp hairs are straight and unbranched, while bee hairs often have multiple branches, perfect for snagging pollen. Since wasps don’t collect pollen, branching hairs are unnecessary.
The great golden digger wasp lives in fields and meadows, especially those with sandy soils. During the months of June through October, the female preys on insects in the Orthoptera order, such as grasshoppers, locusts, crickets, and katydids—all of which go to feed her young.
Building a nest
To build a nest, the female wasp first digs a main tunnel straight down into the ground. From there, she adds a series of cells that radiate from the central entry. In each cell, she places a paralyzed insect, ready to eat. When preparations are complete, she lays a single egg on top of each insect. Once the wasp larva emerges, it gets the full meal deal: an entire insect all to itself. Each adult female lays about 10 eggs in her lifetime.
The adult wasps are commonly found on plants such as Asclepias (milkweed), where they stop for a drink of carbohydrate-rich nectar. They also forage on Eryngium, Monarda, Solidago, and other plants, depending on the season.
Once classified as Apis
I find it interesting that in 1758 Carl Linnaeus, the father of modern taxonomy, first placed this wasp in the bee genus, Apis. In fact, its original name was Apis ichneumonea. Then in 1783 it was re-classified into another genus, Nomada, which are cleptoparasitic bees. The new name became Nomada surinamensis. It wasn’t until 1833 that it was moved into the wasp genus Sphex, and became Sphex aurifluus. Even though it has lots of hair, which is confusing, the fact that it catches insects should have been a dead giveaway that it wasn’t a bee. On the other hand, perhaps they classified specimens in the lab, rather than watching them in the field. I wish I knew.
Honey Bee Suite