Pennsylvania ambush bug

(Phymata pennsylvanica)

Conservation Status
Pennsylvania ambush bug
Photo by Mike Poeppe
  IUCN Red List

not listed


not listed


not listed


There are 17 species of jagged ambush bugs (genus Phymata) that occur in North America north of Mexico. Only two species have been recorded in Minnesota.

Pennsylvania ambush bug is a small, well-camouflaged, ambush bug. It occurs in the United States east of and just west of the Mississippi River and in adjacent Canadian Provinces. A disjunct population has been reported in Colorado. It is rare in Minnesota, where it is at the western extent of its range.

Adults are 5 16 to ½ (7.5 to 12 mm) in length and light colored with dark markings. The light color may be yellow, yellowish-white, yellowish-green, greenish-yellow, or any combination of these. The dark markings are usually dark brown to almost black but are sometimes medium brown, brownish-orange, or brownish-yellow. Males tend to be darker than females.

There are two large compound eyes, one on each side of the head, and two simple eyes (ocelli) on the top of the head (vertex). The antennae have four segments. The last segment is only slightly enlarged (clubbed). The collection of protruding mouthparts (beak) is short, has three segments, and is optimized for sucking.

The exoskeletal plate covering the thorax (pronotum) has jagged, spiny, rear corners. This feature gives the genus its common name. The pronotum usually has four alternating bands, two light and two dark. These may be obscure or appear as a pair of light spots on each side. The plate between the bases of the wings (scutellum) is triangular and shorter than the pronotum.

The abdomen has a flattened, greatly enlarged margin (connexivum). It is more or less diamond-shaped, widest in the middle, and a broadly rounded tip (apex). It is pale with a broad dark band across the widest part. The segments of the connexivum are dilated, though this is difficult to see in photos. The widest segment has angular sides with one corner that sticks out farther than the adjacent segments. This makes the overall shape of the connexivum look distinctly notched, not smooth. Connexiva on abdominal segments 3 and 4 usually do not have a dark marginal spot.

The wings at rest are held folded over the back. They cover only the middle portion of the abdomen, leaving the sides exposed.

The legs are pale. On the front legs the third segment (femur) is greatly enlarged, optimized for grasping large prey. When the front legs are folded, the fourth segment (tibia) fits into a groove on the bottom of the femur. The last part of the leg (tarsus), corresponding to the foot, has three segments.




Total length: 5 16 to ½ (7.5 to 12 mm)


Similar Species


Jagged ambush bug (Phymata americana) connexivum is smooth, not notched at the widest part. The segments of the connexivum are not dilated. It is much more common in Minnesota. On abdominal segments 3 and 4, each connexiva usually has a dark marginal spot.


Open and semi-open areas, including forest edges, farms, meadows, and gardens.




Mid-July to late September




Adults prefer yellow or blue flowers where their camouflage is most effective. They may have the ability to change their colors somewhat in response to their environment. They can capture prey up to ten times their own size.


Life Cycle




Nymph Food


Small insects


Adult Food


Bees, butterflies, flies, day-flying moths, and other true bugs.


Distribution Map



24, 27, 29, 30, 82, 83.




Rare in Minnesota



Hemiptera (true bugs, hoppers, aphids, and allies)  


Heteroptera (true bugs)  






Reduviidae (assassin bugs)  


Phymatinae (ambush bugs)  




Phymata (jagged ambush bugs)  
  Subgenus Phymata  

The genus Phymata was formerly placed in its own family, Phymatidae.






Common Names


Pennsylvania ambush bug









On plants: A comparatively short and stout, narrow or prolonged tip on a thickened organ, as on some fruits and seeds. On insects: The protruding, tubular mouthpart of a sucking insect.



In Heteroptera: the enlarged, flattened margins of the abdomen. Plural: connexiva.



On insects and arachnids, the third, largest, most robust segment of the leg, coming immediately before the tibia. On humans, the thigh bone.



Simple eye; an eye with a single lens. Plural: ocelli.



The exoskeletal plate on the upper side of the first segment of the thorax of an insect.



The exoskeletal plate covering the rearward (posterior) part of the middle segment of the thorax in some insects. In Coleoptera, Hemiptera, and Homoptera, the dorsal, often triangular plate behind the pronotum and between the bases of the front wings. In Diptera, the exoskeletal plate between the abdomen and the thorax.



On insects, the last two to five subdivisions of the leg, attached to the tibia; the foot. On spiders, the last segment of the leg. Plural: tarsi.



The fourth segment of an insect leg, after the femur and before the tarsus (foot). The fifth segment of a spider leg or palp.



The upper surface of an insect’s head.






Visitor Photos

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Alfredo Colon

    Pennsylvania ambush bug   Pennsylvania ambush bug  
    Pennsylvania ambush bug   Pennsylvania ambush bug  
    Pennsylvania ambush bug   Pennsylvania ambush bug  

Mike Poeppe

    Pennsylvania ambush bug   Pennsylvania ambush bug  
    Pennsylvania ambush bug   Pennsylvania ambush bug  
    Pennsylvania ambush bug   Pennsylvania ambush bug  








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Other Videos
  Phymata pennsylvanica drinking nectar

Aug 23, 2020

Sorry for the shakeycam, breathing and verticality. Not everyone is a professional who set up their equipment for an hour under perfect conditions. Some people are just amateurs with a phone and a clip-on macro lens.




Visitor Sightings

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  Alfredo Colon

Location: Albany, NY

Pennsylvania ambush bug  
  Mike Poeppe

Location: 1 mile west of Houston, MN

Pennsylvania ambush bug  
  Mike Poeppe

Location: just west of Houston, MN

Pennsylvania ambush bug  






Created: 8/24/2020

Last Updated:

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