Thyanta custator

Distinguished from the redbanded stink bug (Piezodorus guildinii) by the absence of a long spine protruding between the hind legs on the ventral surface; P. guildinii possesses this spine. Separated from the southern green stink bug (Nezara viridula) by the reddish shoulder band and reddish antennae (N. viridula has reddish bands on antennae but lacks the shoulder band). The green stink bug (Chinavia hilaris) lacks any reddish coloration and is larger. Brown stink bugs (Euschistus spp.) are predominantly brown without reddish markings. The spineless ventral surface is the most reliable character for separating T. custator from P. guildinii when both occur together.

Shield-shaped body typical of Pentatomidae. Adults possess a distinct reddish band across the pronotum (shoulders), the namesake feature. Antennae are reddish in color. The body is generally greenish to yellowish-green. The species lacks the long spine between the hind legs that characterizes the redbanded stink bug (Piezodorus guildinii), a key distinguishing feature. Nymphs resemble adults but are wingless and pass through five instars, increasing in size at each stage.

Agricultural fields, particularly soybean fields; gardens with fruit and vegetable crops; areas with host plants including Lyonia lucida (Eastern fetterbush) in Florida. Associated with legume weeds before colonizing cultivated soybeans.

North America, with records from the eastern and central United States. Documented in Florida, Texas (northeast Texas specifically), and throughout the range of soybean cultivation in the eastern U.S. Also recorded from Hawaii.

Multiple generations per year. Adults colonize soybeans from legume weed hosts when soybeans begin to flower. Active from first pod formation (R3 growth stage) through full seed development (R6), a period lasting up to 7 weeks. Nymphs present in fields indicate reproduction has occurred; presence of nymphs signals established infestation.

Phytophagous; feeds on developing flowers, pods, and seeds of legumes and other plants. Documented hosts include soybean (Glycine max), Lyonia lucida (Eastern fetterbush), and various fruits and vegetables including tomatoes, beans, peaches, pears, apples, pistachios, and almonds. Feeding occurs by piercing plant tissue and sucking juices.

• Glycine max - food plantMajor agricultural host; causes yield loss and quality reduction
• Lyonia lucida - food plantEastern fetterbush; documented host in Florida
• Prunus persica - food plantPeach; feeding causes brown, corky fruit damage
• Solanum lycopersicum - food plantTomato; damage appears as dark pinpricks with discolored areas
• Pyrus spp. - food plantPear; feeding causes depressed, pithy areas
• legume weeds - food plantEarly-season hosts before soybean colonization

Hemimetabolous development. Eggs are barrel-shaped and laid in masses on plants. Nymphs emerge and pass through five instars before becoming winged adults. Nymphs resemble adults but lack wings. Multiple generations develop annually, with populations building first on legume weeds then moving to soybeans.

When disturbed or crushed, releases an unpleasant odor from scent glands. Adults are capable of flight and can re-infest fields after insecticide applications. Mobile within fields, moving among plants. Reproductive behavior includes mating on host plants with eggs deposited on stems and leaves.

Herbivore; acts as agricultural pest in soybean and fruit/vegetable production. Part of food web as prey for generalist predators including spined soldier bug (Podisus maculiventris) and other predatory insects, though chemical defenses deter some predators.

Agricultural pest of economic significance in soybean production, particularly in the eastern United States. Feeding damage reduces yield and seed quality, causes flat pod syndrome, delays crop maturity, and reduces germination of seed beans. Management involves scouting with sweep nets or ground cloths and insecticide application when thresholds are exceeded (36 adults and older nymphs per 100 sweeps, combined with other stink bug species). Subspecies T. c. accerra is specifically referenced in agricultural extension literature for Texas.

• Piezodorus guildiniiRedbanded stink bug; similar reddish band across body but distinguished by long spine between hind legs (absent in T. custator) and smaller size
• Nezara viridulaSouthern green stink bug; green with reddish antennal bands but lacks reddish shoulder band; has short rounded spine between hind legs versus no spine in T. custator
• Chinavia hilarisGreen stink bug; larger, entirely green without reddish markings
• Thyanta pallidovirensRed-shouldered stink bug; very similar congeneric species with thin red band on shoulders; historically confused but distinct species

The species has been historically confused with Thyanta pallidovirens, another "red-shouldered stink bug"; these are distinct species. Some sources may use "Thyanta spp." when referring to agricultural damage, obscuring species-specific identification. The subspecies T. c. accerra is sometimes referenced separately in agricultural literature but is conspecific.

• stink bug
• agricultural pest
• soybean pest
• Pentatomidae
• phytophagous
• North America
• Hemiptera

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Stink Bugs Do It, Too! | Bug Squad
• Bug Squad
• Three's a Crowd: The Saga of Two Stink Bugs and a Bee | Bug Squad
• Kill It Or Let It Live? | Bug Squad
• Soybean Insects: Late-Season Pests (R1 to R7) - AgriLife Extension Entomology
• Behind the Shield | Bug Squad
• New Host Plant Record for the Stink Bug Thyanta custator (Hemiptera: Pentatomidae) in Florida