Jalysus wickhami

Distinguished from the closely related Jalysus spinosus by specific morphological characters detailed in taxonomic keys. Adults possess fully developed wings, while nymphs have wing pads. The combination of spined body, stilt-like legs, and overall body proportions separates it from other Hemiptera. Keys to adults and fifth instars are available in taxonomic literature.

Adults are slender, elongate true bugs with extremely long, stilt-like legs characteristic of the family Berytidae. The body is typically pale to medium brown with darker markings. A key diagnostic feature is the presence of spines on the body, which distinguishes it from similar species. The antennae are long and thread-like, and the beak (rostrum) is slender and curved beneath the head. Fifth instar nymphs can be distinguished from adults by their wing pads and overall body proportions.

Gardens, meadows, and agricultural fields. Associated with sticky plants such as tarweed (Madia elegans) where it navigates resinous or hooked trichomes to prey on trapped insects or other arthropods. Also found on host plants including legumes, grasses, and solanaceous crops.

North America and Central America. In the United States, recorded from every continental state except Alaska, New Hampshire, and Vermont. In Canada, present in British Columbia, Manitoba, Ontario, and Quebec. In Mexico, documented from Baja California Sur, Chihuahua, Coahuila, Durango, Hidalgo, Nuevo León, Tamaulipas, and Zacatecas.

Active from summer through autumn. Populations peak in late summer and early fall, with overwintering likely occurring as adults.

Omnivorous. Feeds on plant juices from legumes, grasses, and tomato plants. Preys on eggs of the tobacco hornworm (Manduca sexta), prepupae and pupae of the parasitoid Cotesia congregata, and tobacco aphids (Myzus nicotianae). Requires a tobacco leaf substrate for long-term survival; animal prey is necessary for egg production.

• Nicotiana tabacum - plant substrateTobacco leaf necessary for long-term survival; provides moisture or nutrients not obtained from prey alone
• Manduca sexta - preyEggs consumed as food source; highly acceptable prey that supports high fecundity
• Cotesia congregata - intraguild preyPrepupae and pupae consumed; represents intraguild predation that may disrupt biological control
• Myzus nicotianae - preyTobacco aphids consumed, though supports lower fecundity than lepidopteran eggs or parasitoid prepupae
• Madia elegans - habitatTarweed; sticky plant that traps insect tourists, providing carrion that attracts predators including J. wickhami
• Solanum lycopersicum - plant food sourceTomato plant; feeding on plant juices can cause unripe fruit to drop
• Fabaceae - plant food sourceLegumes; plant juices consumed
• Poaceae - plant food sourceGrasses; plant juices consumed

Develops through egg and five nymphal instars to adult. Overwinters as adult. In laboratory conditions, females feeding on high-quality prey (Manduca sexta eggs or Cotesia congregata prepupae) produce approximately 100-106 nymphs per female, while those feeding on tobacco aphids produce approximately 24 nymphs per female.

Navigates sticky plant surfaces to access prey. Engages in intraguild predation, consuming other natural enemies within the same trophic guild. Younger parasitoid prepupae are more vulnerable to predation than older pupal stages. Attachment of parasitoid prepupae to host tissue provides partial protection against predation.

Predator and omnivore in agricultural and natural ecosystems. Functions as a biological control agent by preying on pest eggs such as those of Manduca sexta. However, intraguild predation on parasitoids such as Cotesia congregata may negatively impact biological control programs. Presence on sticky plants contributes to a defensive mutualism where trapped insect carrion attracts predators that reduce herbivore damage.

Considered a beneficial predator in some agricultural contexts due to predation on pest eggs. However, feeding on tomato plant juices can cause economic damage by inducing premature fruit drop. Intraguild predation on parasitoids may reduce effectiveness of integrated pest management strategies. Has been studied as a model organism for understanding omnivory and intraguild predation in biological control systems.

• Jalysus spinosusClosely related congeneric species; distinguished by morphological characters detailed in taxonomic keys
• Hoplinus echinatusCo-occurring stilt bug species found on same sticky plants; both navigate tarweed trichomes

• predator
• omnivore
• biological control
• intraguild predation
• agricultural pest
• beneficial insect

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Bring on the Tourists! | Bug Squad
• Great Basin Collecting Trip iReport | Beetles In The Bush
• Stalking tigers in Argentina | Beetles In The Bush
• Let’s make a deal! | Beetles In The Bush
• Effects of diet on longevity and fecundity of the spined stilt bug, Jalysus wickhami
• When good bugs go bad: intraguild predation by Jalysus wickhami on the parasitoid, Cotesia congregata
• Jalysus spinosus and J. wickhami1: Taxonomic Clarification, Review of Host Plants and Distribution, and Keys to Adults and 5th Instars