Nothing says wasps like Pennsylvania wasps. Pennsylvania receives historical credit for being one of the original colonies and then states. Less known is the fact that the first Entomological Society was founded in Philadelphia in 1859, later to become Entomological Society of America in 1904. They’ve been big on bugs ever since.
The early insect interest also translated into members collecting specimens of various species and sending samples to the European taxonomists of the day who often named the species in honor of the state or city where the specimen was found. Take the the Great Black Digger Wasp, pictured at the top of the page. It is formally known as Sphex pensylvanicus.
Spex is a genus of thread waisted wasps, easily identified as a group by the thin waist connecting the thorax and abdomen. Like most wasps, they hunt other insects, with Katydids as their prey of choice.
With the exception of the Rocky Mountains and Pacific Northwest, the Great Black Digger wasp is a common summer wasp throughout the United States. Look for it in Pennsylvania roughly from July thru September. As the name suggests it is usually identified as big blue-black wasp that is often found nectaring on flowers.
There’s often a catch when it comes to wasp identification. Consider the second picture of another thread-waisted Pennsylvania gem, Isodontia Philadelphica. It’s big and black just like the Great Black Digger wasp. Plus it is also found on flowers. Grass carrying wasps is the common name given to the species because of their propensity to be seen carrying grass for their nests. If you see a black wasp in the yard carry grass, that’s a good clue for Isodontia.
Another rule of thumb for differentiating between the two species is looking as the way the wings are situated while the wasp is on the flowers. The top picture shows the wings folded down along the body. That’s usually a sign of Sphex pensylvanicus. The second picture shows the wings at an open angle. That’s usually a sign of Isodontia Philadephica.
Fortunately not all digger wasps are so difficult to identify. The Great Golden Digger Wasp in the picture shows up around the garden at the same time as the Great Black Digger Wasp. The red abdomen and golden hairs on the thorax makes it difficult to misidentify.
Ammophila is another genus of thread waisted wasps that are fairly easy to identify given their large bodies and conspicuous presence on flowers. The black and red body of the wasp in the picture belongs to Ammophilia procera. Nothing to worry about, they are not aggressive and do not sting.
Stinging Wasps: Vespids
Vespids are high on the list of Pennsylvania wasps interest because of their propensity to live around residential areas, build nests and sting. Like most of the Northeast states, the Keystone state has its fair share of stinging wasps, especially in the yellowjacket category.
Generally the yellowjackets break down into two groups, depending on their nest building activities. Five different ground nest building yellowjackets can be found in the state.
- Vespula acadica – Forest Yellowjacket
- Vespula flavopilosa – Downy Yellowjacket
- Vespula germanica – German Yellowjacket
- Vespula maculifrons – Eastern Yellowjacket
- Vespula squamosa – Southern Yellowjacket
- Vespula vidua – Widow Yellowjacket
In another one of the insect naming twists, The Western Yellowjacket (Vespula pensylvanica) is not found in the state.
Three aerial yellowjackets also live in Pennsylvania.
Dolichovespula maculata (Bald-faced Hornet)
Common Aerial Yellowjacket – Dolichovespula arenaria
Northern Aerial Yellowjacket Dolichovespula norvegicoides
In residential areas, their nests can be found between walls in buildings.
Vespa crabro (European Hornet)
Murder hornets found in Washington State recently brought attention to hornets. Fortunately they do not make the list of Pennsylvania wasps. Prior to their discovery, the European hornet was basically the only true hornet in the United States. Their nest building habits are similar to the aerial yellowjackets.
Like the murder hornets, they do prey on honey bees, and other yellowjackets. Because forests and wood are their habitat of choice, they tend not to be a big nuisance in residential areas.
Paper wasps can easily be identified by the presence of their flat or umbrella shaped nests that tend to be build under porch roofs and other places safe from the elements around the home. An ounce of prevention might be the best advice for dealing with them. Using a broom to sweep away the nest when it is first being built is much better than having to deal with a nest of some twenty or more stinging wasps once they hatch from the larval state.
The list shows the most common Pennsylvania wasps that fall into the category. Generally paper wasp species can be identified by the color and patterns on the body, legs and antennae. The picture shows a European paper wasp. The two yellow spots at the top of the thorax are good identification clues.
- Polistes perplexus
- Polistes metricus
- Polistes exclamans
- Polistes dorsalis
- Polistes carolina
- Polistes bellicosus
- Polistes annularis
Potter and Mason Wasps
One of the largest groups of Vespid wasps, the Potter and Mason wasps, get their name based on their nest building habits. Potter wasps are known for their pot like nests and mason wasps often use mud in their nests. Over 250 different species, divided into 27 different genera, have been identified in the United States. Often, but not always, species and genera are regionally based.
Pennsylvania’s potter and mason wasps fit into the Eastern group, with approximately 50 species divided into a dozed different genera. They are normally smaller and non-aggressive wasps, so they don’t raise concerns when found in the yard. One last naming twist, at last count, Parancistrocerus pensylvanicus was not found in Pennsylvania. However there records of it in neighboring New York. Perhaps one day it will be discovered in the state.
The large number of species makes for some identification problems. Often, again, not always, they have black, yellow or red bodies with distinct black, yellow, red or white stripes (depending on body color). The top picture shows Euodynerus crypticus, a nice looking red species found in the Eastern half of the United States.
The Fraternal potter wasp in the picture shows another helpful identification clue for some potter and mason wasps. Bugguide describes it as, the “First two abdominal segments forming a tapered petiole linking abdomen and thorax” for species in the Eumenes, Zethus, Minixi, and Zeta genera.
Potter and Mason wasp enthusiasts can use the following list to narrow down their search for specific species in the state.
Parancistrocerus pensylvanicus (not found in PA)
More Pennsylvania Wasps
Apart from specialists, there’s not much identification expertise for the group of wasps in the Ichneumon category.
Ichneumon wasps divide into two families:
- Family Braconidae – Braconid Wasps
- Family Ichneumonidae – Ichneumon Wasps
Identifying them as a group can be fairly straightforward. Physically they often have thin bodies with long antennae and extended tails, formally called Ovipositors. Identifying them to the species is difficult, due mostly to their sheer numbers. Around five thousand species are placed in the Family Ichneumonidae and another 1700 species in the Braconid family. Literally hundreds of different species can be found in Pennsylvania.
With very few exceptions they do no sting humans, and they are not aggressive. So, mostly the average insect enthusiast identifies them at a very general level. For interested individuals, wing pattern differentiates the two families, with Braconid wasps lacking a defined cell at the bottom of their forewings.
The picture shows a species called Trogus pennator. Look for them around swallowtail butterflies because they use the caterpillars as hosts and food for their young.
The button to wasps at the top of the page leads to many more pictures and identification tips for a variety of additional wasp families not covered in this brief overview.