Kelly’s Field Notes
Common Name: Stink bugs, Shield bugs
Order: Hemiptera
Family: Pentatomidae
Genus: There are around 940 genera of stink bugs worldwide (Wikipedia Contributors, 2019)
Interesting Species: There are around 4,700 extant (currently living) species of stink bugs worldwide, of which more than 200 are found in North America (Missouri Department of Conservation, 2025).
Green Stink Bug (Chinavia hilaris) - found throughout the Americas, it is a striking green with yellow edges.
Forest Bug / Red-legged Shield Bug (Pentatoma rufipes) - found throughout Europe, this shield bug changes color with the seasons! In the Fall it is dark brown, but lightens in color during the Summer (Wikipedia Contributors, 2025).
Custodian Shield Bug (Arma custos) - found throughout western Europe, this species is predatory and commonly used in pest control.
Red-banded Stink Bug (Piezodorus guildinii) - found throughout Southern, Central, and North America it is a common crop pest species.
The Brown Marmorated Stink Bug (Halyomorpha halys) - introduced species considered a pest in much of North America, native to Asia
Description:
Adult pentatomids, or stink bugs, are shield shaped (their other common name), stocky, true bugs. The largest species, the giant strong-nosed stink bug (Alcaeorrhynchus grandis), can reach 2.5 cm (0.98 in) in length (Bug Guide, 2025). The smaller species, such as Trichopepla semivittata, can be as tiny as 5 mm in length and up to 8 mm (0.19 - 0.31 in) (Bug Guide, 2025). They represent many colors of the rainbow, often bright reds, oranges, greens, blues, and other iridescent hues. Some also blend in well with their environments, sporting cuticles of browns, tans, and subdued greens. Most have interesting patterns and markings, which may aid in catching the eye of predators and alerting them to their aposematism. Adults have fully functional wings, and like many insects we’ve covered on the podcast they can fly but they look ridiculous doing so.
Nymphs tend to also be brightly colored though rounder in shape and lacking full wings (they have stubby wing pads). Many are bright red or orange with black patterns and markings.
Life Cycle:
Female pentatomids lay their eggs on the underside of plant leaves, in small clusters of 20 to 30 eggs, sometimes more or less depending on the size of the female. The eggs take about a week or longer to hatch, depending on environmental temperature and stink bug species (Beers and Marshall, 2017; Squitier, 2024). Most nymphs are plant feeders, feeding on a variety of plants, and often in conflict with humans over vegetables and other crops. Many species feed on a wide variety of plants, for example the brown sting bug (Euschistus servus) feeds on at least 70 different plant species. The damage caused by the feeding not only harms the plant through tissue damage, but opens it up to infection through disease. Some species, such as the spined soldier bug (Podisus maculiventris), are predators, feeding on other arthropods (University of California, 2025). Whether they are munching on plants or fellow bugs, they use their proboscis to inject digestive enzymes into their food source, then suck out of the liquified innards. The younger the instar, the softer the tissue needs to be for penetration, as the instar increases or when they have reached adulthood they can feed on harder plants and arthropods (North Carolina State University, 2025). Sometimes the damage is very noticeable on fruits, causing a brown scarring called cat-facing scars because they resemble a cat’s face (The Bug Lady, 2017). Nymphs go through 5 instars in about 55-45 days depending on species and temperature, afterwards molting into adults. Adults feed on much of the same foods as they did as nymphs, only their proboscis is stronger and more able to penetrate harder surfaces.
Stink bugs are well known for their ability to communicate via vibrations, which we’ve discussed before in other episodes (plant hopper for example). Research of the Brazilian stink bug (Euschistus hero) highlights that this species communicates through several different forms of sound: stridulation (rubbing body parts together), tremulation (vibrating part or all of their body and forcing that vibration into the substrate or plant they are standing on), percussion (tapping their feet on the substrate or plant), and buzzing (vibrating their wings) (Kavčič et al., 2013; Čokl et al., 2019; Čokl et al., 2021). The vibrations are picked up by fine hairs (setae) on the legs and abdomen of the stink bug. During mating season males and females will sing a duet! In some species, male pheromones elicit the first song from females, in other species males begin the song and females join in until they locate each other to mate (Čokl et al., 2019).
The brown marmorated stink bug as an example invasive species:
The brown marmorated stink bug (Halyomorpha halys) is a common stink bug native to China, Japan, and Korea (Pennsylvania State Extension, 2025). It is an invasive species throughout North America and parts of Europe. In the U.S., they were first found in 1998 in Allentown, Pennsylvania. The stink bugs spread quickly due to their generalist feeding behavior on multiple crops (over 170 species) and the very common behavior of overwintering within homes and other buildings (University of California, 2025). They often aggregate in attics, window frames, siding gaps, and inside walls. While they are not dangerous and do not bite, if disturbed all stink bugs emit foul odor to scare off predators.
In order to combat the brown marmorated stink bug, the Samurai wasp (Trissolcus japonicus) has been introduced to the U.S. The Samurai wasp is an obligate parasitoid of brown marmorated stink bug eggs. The wasp lays her eggs within the eggs of the stink bug, the wasp larvae then hatches and consumes the stink bug nymphs before they can hatch (Quinn and Nixon, 2021). The samurai wasp is a very effective control measure of the brown marmorated stink bug. In their native range, a samurai wasp can kill up to 80% of stink bug eggs, usually infecting all eggs in an egg mass (Yang et al. 2009).
Super Powers:
Stinky - stink bugs have specialized glands in their thorax that store a chemical mixture (mostly unsaturated aldehydes, which smell like rotting fruit or a gross greasy scent). They can actively release the mixture or it automatically is released if they are crushed.
Communication - stink bugs can communicate via a variety of vibrational songs.
Super Piercing - stink bugs, like all true bugs, have a piercing proboscis, able to penetrate plants and other insects.
Aggregation - stink bugs are often found together in large aggregations, especially when overwintering.
Stink Bugs in Culture -
In India, when Udonga montana, a bamboo-feeding stink bug called thangnang, becomes too plentiful, locals collect and eat them. Hot water is poured over the bugs and the oil that rises from their bodies is collected and used as cooking oil. Their bodies are ground into a thick protein rich paste used to feed animals (The Guardian, 2025).
Stinkbugs are an enemy in the video game Grounded.
References:
Beers, Elizabeth H., and Adrian T. Marshall. Brown Marmorated Stink Bug. Washington State University, 2017, treefruit.wsu.edu/crop-protection/opm/brown-marmorated-stink-bug/.
“Brown Marmorated Stink Bug.” Pennsylvania State Extension, 2025, extension.psu.edu/brown-marmorated-stink-bug.
Čokl, Andrej, Alenka Žunič Kosi, and Raul Alberto Laumann. "Stink bug communication with multimodal signals transmitted through air and substrate." Emerging science journal 3.6 (2019): 407-424.
Čokl, Andrej, et al. "Stink bug communication and signal detection in a plant environment." Insects 12.12 (2021): 1058.
Guardian staff reporter. ““We’ve Been Eating It for More than 100 Years”: How One Community Turns Stink Bug Infestations into Lunch.” The Guardian, 21 Nov. 2025, www.theguardian.com/environment/2025/nov/21/turning-stink-bug-infestations-into-lunch-india-the-alternatives.
Kavčič, Andreja, et al. "Tremulatory and abdomen vibration signals enable communication through air in the stink bug Euschistus heros." PLoS One 8.2 (2013): e56503.
Quinn, Nicole F., and Laura J. Nixon. “Samurai Wasp (Trissolcus Japonicus).” Cornell Integrated Pest Management, 2021, cals.cornell.edu/integrated-pest-management/outreach-education/fact-sheets/samurai-wasp-trissolcus-japonicus. .
“Species Alcaeorrhynchus Grandis - Giant Strong-Nosed Stink Bug.” Bugguide.net, 2025, bugguide.net/node/view/33917. Accessed 20 Nov. 2025.
“Species Trichopepla Semivittata.” Bugguide.net, 2025, bugguide.net/node/view/36302. Accessed 20 Nov. 2025.
Squitier, Jason M. “Southern Green Stink Bug, Nezara Viridula (Linnaeus) (Insecta: Hemiptera: Pentatomidae).” Ask IFAS, University of Florida, 2024, edis.ifas.ufl.edu/publication/IN142.
“Stink Bugs.” Missouri Department of Conservation, 2025, mdc.mo.gov/discover-nature/field-guide/stink-bugs.
“Stink Bugs in NC Agriculture.” NC State Extension, North Carolina State University, 2025, www.ces.ncsu.edu/wp-content/uploads/2013/04/.
“Spined Soldier Bug Podisus Maculiventris.” Agriculture and Natural Resources, University of California, 2025, ipm.ucanr.edu/natural-enemies/spined-soldier-bug/#gsc.tab=0.
The Bug Lady. “Brown Stink Bug (Family Pentatomidae).” College of Letters & Science Saukville Field Station, University of Wisconsin Milwaukee, 2017, uwm.edu/field-station/bug-of-the-week/brown-stink-bug-family-pentatomidae/.
Wikipedia Contributors. “Pentatomidae.” Wikipedia, Wikimedia Foundation, 9 Oct. 2019, en.wikipedia.org/wiki/Pentatomidae.
Wikipedia Contributors. “Forest Bug.” Wikipedia, Wikimedia Foundation, 17 Aug. 2025, https://en.wikipedia.org/wiki/Forest_bug
Yang, Zhong-Qi, et al. "A new species of Trissolcus (Hymenoptera: Scelionidae) parasitizing eggs of Halyomorpha halys (Heteroptera: Pentatomidae) in China with comments on its biology." Annals of the Entomological Society of America 102.1 (2009): 39-47.