Phymata americana

Geographic Range

Jagged ambush bugs (Phymata americana) are native to North and Central America. Their distribution stretches from Southern Canada, through the United States and Mexico, to Guatemala. ("iNaturalist", 2021; ITIS, 2021)


Jagged ambush bugs live in areas with open or semi-open flower fields, but they are occasionally found on inflorescences that are not in fields. Jagged ambush bugs prefer flowers that match their body color, such as goldenrod. They can be found from low elevations up to higher mountain foothills, although no specific elevation range is reported. Jagged ambush bugs live in subtropical and temperate biomes in which fields of flowers grow. They often inhabit suburban and agricultural areas, especially when native plant communities also persist in the area. ("iNaturalist", 2021)

Physical Description

Jagged ambush bugs are an average of 9 mm long and exhibit a variety of colors that helps them camouflage with local wildflowers. They can be white, yellow, or green, and often have some black or dark brown markings on each of their body segments. As their name suggests, jagged ambush bugs have exoskeletons with sharp angles, especially on the edges of their heads and thoraces, giving them a "jagged" appearance. Their bodies are diamond shaped, with flattened abdomens and wings that rest on top of each other along their midlines. Jagged ambush bugs have small antennae with clubbed ends and two large, yellow, compound eyes positioned laterally on their heads. Their legs are pale in color and the femurs of their forelegs are thicker and well-adapted for grasping prey items. Jagged ambush bugs undergo incomplete metamorphosis, meaning nymphs are physically similar to adults, although they do not have wings or dark markings until adulthood. Sexual dimorphism is present in that female jagged ambush bugs are generally larger than males. Females also have larger claws and darker markings compared to males. (Mason, 1977; Valo, 2021)

  • Sexual Dimorphism
  • sexes alike
  • female larger
  • Range length
    7.5 to 12 mm
    0.30 to 0.47 in
  • Average length
    8.75 mm
    0.34 in


Jagged ambush bugs experience only one generation per year. First instar nymphs emerge from their eggs in early spring and experience five molts, or instars, before they reach adulthood. Jagged ambush bugs develop darker coloration with every molt, but do not gain functional wings until adulthood. Fifth instar nymphs have wing pads, but these are unusable for flight. Jagged ambush bugs also increase in size with each molt. (Punzalan, 2021)


Jagged ambush bugs are polygynandrous, meaning both males and females have multiple mates during a breeding season. Females are typically sedentary, whereas males actively seek out females during breeding season. Jagged ambush bug males use courtship behaviors that involve sounds and touch to attract females. During copulation, males exhibit mate-guarding behaviors, actively deterring any competitors that may approach. Male jagged ambush bugs with darker coloration are generally more successful in finding mates. It is suspected that darker colors help males warm up faster in the morning, as darker colors absorb more heat energy from the sun. By warming up faster, darker males have more time to find females and mate before lighter males are active. ("iNaturalist", 2021; Mitton, 2015; Punzalan and Rowe, 2013)

There is limited knowledge regarding the reproductive processes of jagged ambush bugs. They reproduce sexually, with only one new generation per year. Their breeding season extends from the end of July to September. Females and males mate frequently during this time, and females lay small clutches of eggs multiple times throughout their breeding season. Sexual maturity for these insects occurs when they molt from their fifth instar into their adult stage, which occurs around 3 to 4 months after hatching. Adults survive through breeding season until it gets colder, in fall or winter. (Punzalan, 2021; Punzalan and Rowe, 2013; Punzalan, et al., 2008)

  • Breeding interval
    Jagged ambush bugs breed multiple times during the breeding season.
  • Breeding season
    The breeding season of these insects is from the end of July to the middle of September.
  • Range eggs per season
    8 to 15
  • Range age at sexual or reproductive maturity (female)
    3 to 4 months
  • Range age at sexual or reproductive maturity (male)
    3 to 4 months

There is little information regarding parental investment in jagged ambush bugs, but they do exhibit a few behaviors worth noting. For example, males exhibit mate guarding, protecting females from competitors while mating. This improves their chances of reproductive success. Females protect the eggs they lay by coating them in a foamy substance that they excrete. This substance hardens over time, keeping eggs dry and safe from predators. (Brunet, 2021; "iNaturalist", 2021)


Jagged ambush bugs produce one new generation per year. Eggs that females lay in fall do not hatch until early spring. Jagged ambush bugs live six to eight months in total. After hatching, jagged ambush bug nymphs take 3 to 4 months to progress through five instars before reaching adulthood. Adults live until their breeding season ends, before colder weather comes in fall or winter. (Punzalan, 2021)

  • Typical lifespan
    Status: wild
    6 to 8 months


Jagged ambush bugs are solitary hunters that tend to stay in the same patch or field of flowers to hunt and reproduce. They are poor fliers and females are mostly sedentary. However, adult males become more active during the breeding season, flying or climbing between flowers in search of females. Jagged ambush bugs are diurnal, and at night they are very inactive. They generally rely on solar energy to warm up before becoming active during the day. ("iNaturalist", 2021; Mitton, 2015)

Home Range

There is little information on home ranges for jagged ambush bugs. However, they are not highly mobile, often spending their lives in one patch or field of flowers.

Communication and Perception

Jagged ambush bugs have setae, or small hair-like protrusions on the exoskeleton, that are sensitive to touch. Their setae help jagged ambush bugs sense vibrations from sounds or movement around them. Jagged ambush bugs have large, compound eyes that are sensitive to light and visual cues in their environments. They use their eyes to detect prey, predators, and changes in light availability during the day or throughout the year. Jagged ambush bugs also detect chemical cues with their antennae. They emit and receive pheromones and other chemicals to relay information to conspecifics or other species. (NC State, 2015)

Communication is particularly important for mating. Males attract females using physical or auditory communication, which females evaluate to determine if males are suitable mates. ("iNaturalist", 2021)

Food Habits

Jagged ambush bugs are sit-and-wait predators that hunt a variety of insects. Most of these are flying insects that visit flowers, such as bees and wasps (order Hymenoptera), beetles (order Coleoptera), butterflies and moths (order Lepidoptera), and flies (order Diptera). They also prey on flying moths (genus Ctenucha), tumbling flower beetles (family Mordellidae), and plasterer bees (family Colletidae). Jagged ambush bugs are reported to eat species such as honeybees (Apis mellifera), house flies (Musca domestica), drone flies (Eristales tenax), blowflies (Calliforidae), and flower flies (Syrphidae). They also opportunistically eat other arthropods that cross their paths. ("iNaturalist", 2021; Mason, 1977)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods


Jagged ambush bugs serve as prey for large vertebrates like birds and rodents, as well as small invertebrates like spiders and other insects. However, there is little information regarding the specific predators of jagged ambush bugs. Jagged ambush bugs have cryptic coloration that camouflages them with the flowers on which they wait for prey. This keeps them safe from predators and also increases their effectiveness as hunters.

Jagged ambush bugs prefer to live on flowers that match their body color, but their coloration shows phenotypic plasticity. This means that, to a certain degree, the body color of jagged ambush bugs is subject to change over time depending on environmental conditions, such as the types of flowers in an area. It is also possible that their color changes with each molt, since the color of some plant flowers can change as plants grow. (Brunet, 2021; "iNaturalist", 2021)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Jagged ambush bugs are important insect predators in their environments. They are opportunistic, sit-and-wait predators, eating anything that visits the flowers on which they are hiding, as long as they can grab it with their raptorial front legs. Because of their varied diet, jagged ambush bugs likely help control the populations of multiple pest species. Additionally, they are a food source for other animals, such as other predatory arthropods, birds, and small mammals. (Boggs, 2020; Brunet, 2021)

Jagged ambush bugs have specific plants on which they hide when hunting. They have a commensal relationship with these host species, since jagged ambush bugs derive a benefit, but have seemingly no impact on plants they use. Jagged ambush bugs prefer plants with flowers that match their coloration, which can be yellow, green, or white. Some of the plants that jagged ambush bugs frequently use include Canada goldenrod (Solidago canadensis), wild teasel (Dipsacus fullonum), Queen Anne's lace (Daucus carota), sunflowers (genus Helianthus), blazing stars (genus Liatris), and most daisies (genus Bellis). Such plants typically occur at high densities, which makes it possible for jagged ambush bugs to move between flowers with similar colors. (Boggs, 2020; Brunet, 2021; "iNaturalist", 2021)

Species Used as Host
  • Canada goldenrod (Solidago canadensis)
  • Wild teasel (Dipsacus fullonum)
  • Queen Anne's lace (Daucus carota)
  • Sunflowers (genus Helianthus)
  • Daisies (genus Bellis)
  • Blazing stars (genus Liatris)

Economic Importance for Humans: Positive

Jagged ambush bugs have no known positive economic impacts on humans. However, they do prey on pest species, which can be beneficial for agriculture and recreational horticulture. (Brunet, 2021)

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

Jagged ambush bugs have no known negative economic impacts on humans. However, they may bite when handled or threatened. They do have venom, which can cause pain or irritation if bitten. Furthermore, jagged ambush bugs eat species of plant pollinators, since they are generalist predators that wait on flowers. (Brunet, 2021)

  • Negative Impacts
  • injures humans

Conservation Status

Jagged ambush bugs are common throughout their range. They have no special status on the IUCN Red List, CITES appendices, U.S. Federal List, and State of Michigan List.


Amy Bagby (author), Colorado State University, Amy Bagby (editor), Colorado State University, Genevieve Barnett (editor), Colorado State University, Galen Burrell (editor), Special Projects.



living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map


uses sound to communicate


living in landscapes dominated by human agriculture.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


an animal that mainly eats meat


uses smells or other chemicals to communicate


having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

  1. active during the day, 2. lasting for one day.

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females


union of egg and spermatozoan


An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

male parental care

parental care is carried out by males


A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.


having the capacity to move from one place to another.


This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.


reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.


chemicals released into air or water that are detected by and responded to by other animals of the same species


the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


lives alone


living in residential areas on the outskirts of large cities or towns.


uses touch to communicate


Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.


A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.


an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).


movements of a hard surface that are produced by animals as signals to others


uses sight to communicate


2021. "iNaturalist" (On-line). Phymata americana aka Jagged ambush bug. Accessed November 09, 2021 at

Boggs, J. 2020. "Ambush Bugs: A Pollinator Peril" (On-line). Accessed November 17, 2021 at

Brunet, D. 2021. "AMBUSH BUGS Phymata spp. and others in subfamily Phymatinae (ambush bugs)" (On-line). Missouri Department of Conservation. Accessed November 17, 2021 at

ITIS, 2021. "Phymata americana Melin, 1930" (On-line). Integrated Taxonomic Information System. Accessed November 09, 2021 at

Mason, L. 1977. Prey Preferences and Ecological Sexual Dimorphism in Phymata americana Melin. The American Midland Naturalist, 97:2: 293-299. Accessed November 17, 2021 at

Mitton, J. 2015. "Why are male jagged ambush bugs darker than females?" (On-line). Colorado Arts and Sciences Magazine Archive. Accessed November 18, 2021 at

NC State, 2015. "Insect Communication" (On-line). NC State Agriculture and Life Sciences. Accessed November 18, 2021 at

Punzalan, D. 2021. "Ambush Bugs" (On-line). Accessed November 17, 2021 at

Punzalan, D., F. Rodd, L. Rowe. 2008. Contemporary sexual selection on sexually dimorphic traits in the ambush bug Phymata americana. Behavioral Ecology, 19:4: 860-870. Accessed November 18, 2021 at

Punzalan, D., L. Rowe. 2013. Ecological correlates of daily mating frequency in a wild population of ambush bugs. Ecological Entomology, 38:4: 429-432. Accessed November 18, 2021 at

Valo, J. 2021. "Minnesota Seasons" (On-line). jagged ambush bug (Phymata americana). Accessed November 17, 2021 at