Abstract

The species of Gymnosomatini (Diptera: Tachinidae) are specialized to attack stink bugs (Hemiptera: Pentatomidae). Some of these flies, such as those in the genus Trichopoda Berthold, are conspicuous and represent target species to study with citizen science. Here we report for the first time the distribution range of T. (Galactomyia) pictipennis Bigot, a newly introduced biological control species of tachinid for use against stink bugs in Chile using data obtained through the citizen science method. Additionally, we update the distribution of T. arcuata (Bigot), a native biological control species of tachinid, and assess the grade of overlap between the flies and their main stink bug hosts. We obtained data regarding the occurrence of flies and stink bugs from the citizen science program "Moscas Floricolas de Chile," from Facebook groups, and from iNaturalist. We standardized our data to avoid temporal, spatial, and geographic biases. We report the extent of occurrence (EOO) and area of occupancy (AOO) for each fly and stink bug species. The EOOs for T. pictipennis and T. arcuata are 85,474 km(2) and 20,647 km(2) through central Chile ecosystems, respectively. The EOO of T. arcuata is overlapped by 53% with the introduced species. Trichopoda pictipennis has a high percentage of overlap with the EOO of Nezara viridula Linnaeus (61%), whereas T. arcuata has low percentages of overlap with different native Acledra species and with N. viridula. We discuss the potential of citizen science to detect (1) areas with higher diversity or gaps of occurrences, (2) new biological control agents, (3) prey records, (4) negative impacts on non-target species, (5) changes in composition at long-term, and (6) areas to promote conservation biological control in agricultural landscapes.