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Certain species of assassin bugs have evolved the sticky trap strategy to capture prey using adhesive substances on their legs. The resin bug Heniartes stali collects a sticky exudate from the trichomes of a blackberry plant and smears its legs with it through an intriguing gathering process. We report laboratory experiments aimed at understanding the capture behavior of H. stali when it encountered three insect prey species with different mobility: the coleopteran larvae of Tribolium castaneum, a slow-moving organism; workers of the aggressive and highly mobile ant Camponotus rufipes; and winged prey, the fly Drosophila sp. Bugs stalked prey approaching within reach of their forelegs. After the bug threw forwards its forelegs, the prey became stuck and was subsequently held firmly by clutching with the aid of the middle legs, also smeared with trichome exudate. The bugs took longer to catch ants and immobilize them than larvae. Attacks on flies were unsuccessful because of flight escape before contact with H. stali occurred. A clear association between exudate harvesting and prey-capture behavior was unequivocally demonstrated. This is the first detailed description of a sticky leg trap from harvested plant exudate in Heniartes and related prey-capture behavior.

Long term infection of Helicobacter pylori (Hp) virulent strains is a key factor in the genesis of human gastric cancer, and so are certain dietary proinflammatory and genotoxic compounds. Carcinogenic bracken fern (Pteridium spp.) is one of these. Toxins from this plant are consumed as bracken culinary preparations, through milk and meat of bracken-exposed livestock, and drain waters from bracken swards. Bracken toxin ptaquiloside (PtQ), a suspected human carcinogen, elicits complex responses in animals leading to death. PtQ and Hp might cooperate in gastric pathologies. This paper presents an hypothesis on PtQ-Hp association leading to the enhancement of carcinogenesis in the human gastric environment that might explain the high gastric cancer incidence and death rates among Hp-infected people living in bracken zones at two levels: (1) The macroscopic scale comprising the flow of PtQ in the human diet. (2) the microscopic scale encompassing (A) gastric luminal medium; (B) gastric mucus structure and mucin degradation elicited by Hp; (C) bacterial pH gradient modification of the gastric mucosa that favors PtQ survival and its penetration into epithelial tissue; (D) combined PtQ/Hp effects on gastric immune and inflammatory responses; (E) PtQ-Hp complementary activity at selected cell signaling cascades and genome disturbance.

Resin bugs are a group of reduviids which collect viscous substances from plants with their legs and use them as an aid in prey capture and to protect eggs against predators. We designed the present investigation to examine aspects of the natural history and biology of Heniartes stali (Wygodzinsky) in association with Rubus cf. adenotrichos (Schltdl.), an Andean wild blackberry covered with trichomes that secrete a sticky fluid. We surveyed the occupancy of this plant by the bugs in five localities in the Venezuelan Andes and the sticky material source was determined. Nymphs, and in minor proportion, adults were frequently found on the blackberry plants. We also document the harvesting and handling of this exudate by H. stali under laboratory conditions. The bugs invested several hours to gather the sticky material using the forelegs, transferred it to the midlegs, and subsequently stored it in a conspicuously hairy area of the hindlegs. Portions of the accumulated material were smeared on the genital are...