The family Sphecidae, thread-waisted wasps technically belongs to a larger grouping call apoid wasps, the progenitors of the bee family. North America hosts about 125 species divided into 11 genera. The thin body piece that connects the thorax and the abdomen explains the common name.
Most of the species can be found around residential areas and gardens, making them a familar spring, summer and fall sighting. Unlike the more aggressive and stinging vespids, as a group they are not considered harmful. In fact, they are beneficial insects because they prey on many pest insects. Here’s a quick run down of the most common species found in the United States. The wasps button leads to presentations covering additional wasp species.
About one-half of the species belong to the Ammophila genus characterized by long, thin bodies often with a mixture of black and red bodies and legs. Common across the United States, identifying them past the level of genera can be very problematic. Consider a recent press release. “The UC Davis Insect Ecology Group has named Arnold Menke’s publication on “The Ammophila of North and Central America (Hymenoptera, Sphecidae)” as one of the best papers of 2020.”
“The North and Central American species of Ammophila are described and a key provided for their identification. Sixty-nine species are recognized, of which 62 are known from North America. The other seven are known only from Mexico. Four new species are described, hallelujah from northeastern California, linda from southern California, mexica and zapoteca from south central Mexico.”
What follows is a brief and tentative run down for some basic identification clues to help differentiate a few different species. All things being equal, it’s more than adequate to identify them at the genus level.
The first potential identification mix up deals with a Southwest and California species called Ammophila alberti. Note the red legs in the picture.
Southern California also has a very similar looking species, silver around the thorax, slight darkening at the tip of the otherwise red abdomen. However, the legs are black. So, the best identification guess is that it is a different, unnamed species.
The desert Southwest provides a perfect habitat for sand wasps. Additional Southwest Ammophilia species also show mostly red bodies and red legs. One exception to the rule is Ammophila wrighti a very distinct species more brown than red in color.
Easterners usually focus on three different species that are fairly common and have some physically divergent identification clues. Ammophila nigricans, for example has very dark wings and no markings on the thorax.
Ammophila pictpennis, another Eastern Species. can be identifies by the orange wings and absence of silver marks on the thorax.
Finally, the presence of silver marks on thorax is used as the basic field identification clue for Ammophila procera.
Only one species in the Eremnophila genus and it’s fairly easy to identify. Abundant east of the Rocky Mountains. Look for it in the summer months. In the warmer climates it may hang around a bit longer.
Cutworm Wasps (genus Podalonia) are primarily western species that look very similar to Ammophila The thread part of the waist is more distinctly curved at the abdomen. there are both red and black bodies and black bodies species.
The remaining thread-waisted wasp species also have a few difficult identification issues, but not nearly as many as the Ammophilia. Take the Yellow-legged Mud Dauber, for example. A black body with yellow markings on the legs makes for fairly easy identification. They can be found near mud holes collecting mud for nest building. They paralyze a variety of spiders to serve as food for their larvae.
A few blue wasps have been documented. The Blue Mud wasp (Chalybion californicum) gets credit for using Black Widow spiders as the larval food. They are fairly common across the United States.
For comparison, here’s the Steel Blue Cricket Hunter.
Often the genus Sphex stands in as the representative of the thread-waisted wasps. Various species are ubiquitous in summer gardens across the country, starting with the Great Black Digger wasp. It’s above average size and black body might make for easy identification. In order not to confuse it with another common black wasp species, the grass carrying wasp, look at the way the wasp holds its wings when nectaring on flowers. Great Black Digger wasps usually fold their wings down their bodies as shown in the picture.
Great Golden Digger Wasps arrive in the garden at the same time as the Great Black Digger wasps. The yellow fuzzy thorax and red abdomen make for great field identification clues.
The Great Black Digger Wasp and Great Golden Digger Wasp are the more common of the digger wasps. The Katydid wasp in the picture shows a similarity to the Great Black digger wasp except for the brown legs.
Golden-reined Digger Wasps partially resemble Great Golden Digger Wasps.
Seven thread-waisted wasps in the genus Prionyx can be found from coast to coast . They are smaller than the digger wasps and mud daubers with a shorter petiole. The picture shows a basic red version. There is also a black version.
Six different grass carrying wasps (Isodontia – Grass-carrying Wasps) are in the United States. Hair color on thorax is a good first identification clue for many of them. Light color hair means Mexican Grass Carrying Wasp or I. apicalis
Dark hair suggests either a Brown-legged Grass Carrying Wasp or I philadelphica. The brown legs on the wasp in the picture help complete the identification.
Two her Isodentia species show golden golden hair on the thorax. Along with the golden hair, I. elegans also has a red color to the abdomen aking it possible to initially confused it with the great golden digger wasp. It’s very widespread. The other species, I. exornata has a Southeast range.