Toxicity of clothianidin to common Eastern North American fireflies

Abstract

Background Previous research suggests that fireflies (Coleoptera: Lampyridae) are susceptible to commonly used insecticides. In the United States, there has been a rapid and widespread adoption of neonicotinoid insecticides, predominantly used as seed coatings on large-acreage crops like corn, soy, and cotton. Neonicotinoid insecticides are persistent in soil yet mobile in water, so they have potential to contaminate firefly habitats both in and adjacent to application sites. As a result, fireflies may be at high risk of exposure to neonicotinoids, possibly jeopardizing this already at-risk group of charismatic insects. Methods To assess the sensitivity of fireflies to neonicotinoids, we exposed larvae of Photuris versicolor complex and Photinus pyralis to multiple levels of clothianidin-treated soil and monitored feeding behavior, protective soil chamber formation, intoxication, and mortality. Results Pt. versicolor and Pn. pyralis larvae exhibited long-term intoxication and mortality at concentrations above 1,000 ng g−1 soil (1 ppm). Under sub-lethal clothianidin exposure, firefly larvae fed less and spent less time in protective soil chambers, two behavioral changes that could decrease larval survival in the wild. Discussion Both firefly species demonstrated sub-lethal responses in the lab to clothianidin exposure at field-realistic concentrations, although Pt. versicolor and Pn. pyralis appeared to tolerate higher clothianidin exposure relative to other soil invertebrates and beetle species. While these two firefly species, which are relatively widespread in North America, appear somewhat tolerant of neonicotinoid exposure in a laboratory setting, further work is needed to extend this conclusion to wild populations, especially in rare or declining taxa.

Physiological Responses of the Firefly Pyrocoelia analis (Coleoptera: Lampyridae) to an Environmental Residue From Chemical Pesticide Imidacloprid

“…The imidacloprid exposure concentration used in the present study also represented the residual concentrations of imidacloprid in the environment in some regions (0.1 mg/L to over 0.32 mg/L) ( Van Dijk et al, 2013 ; Chen M. et al, 2015 ; Li et al, 2018 ). The larvae of P. analis exposed to a dose of 0.1 mg/L imidacloprid showed an obvious toxic response within 6 h of exposure, however, only a few died within 72 h. Pearsons et al (2021) also obtained a similar result after measuring the toxic response and mortality of Eastern North American fireflies when exposed to clothianidin.…”

“…Fireflies are an ideal environmental indicator species for pollution and insecticides due to their susceptibility to pesticides and flashing behaviors ( Lewis et al, 2020 ; Colares et al, 2021 ; Pearsons et al, 2021 ; Zhang et al, 2021 ). Thus, our study investigated the physiological and histological changes in response to imidacloprid and characterized their luminant characters following the imidacloprid exposure.…”

“…Pyrocoelia analis belongs to the order Coleoptera, family Lampyridae ( Fu, 2014 ) and is a common local firefly in most mountain regions of west China. Fireflies are very sensitive to pollution and insecticides ( Pearsons et al, 2021 ) and fireflies have been used as ecological indicators due to their diverse luminescence and flashing behaviors ( Fu et al, 2017 ; Zhang et al, 2019 ; Zhang et al, 2021 ). Over the past decades, wild firefly populations have declined globally, and some species were even threatened with extinction ( Fu et al, 2017 ; Chatragadda, 2020 ; Lewis et al, 2020 ; Mbugua et al, 2020 ; Pearsons et al, 2021 ), and pesticide use was considered as one of the most serious threats to fireflies ( Lewis et al, 2020 ).…”

Predicting the potential suitable distribution area of Emeia pseudosauteri in Zhejiang Province based on the MaxEnt model

“…The annual Emeia pseudosauteri glow show staged in the local area is as bright and spectacular as a night sky covered with stars, and this light can induce a strong visual impact and emotional response in viewers, attracting a large number of tourists to come to the viewing experience, gradually forming an ecotourism project in the local area with the Emeia pseudosauteri viewing experience as the main focus, and bringing tangible economic bene ts to the people 22 . However, the excessive interference of human activities, domestic sewage, pesticides, night lights, road hardening, and the proliferation of tourists are causing damage and pollution to the existing habitat of Emeia pseudosauteri in Zhejiang Province, making the survival and reproduction of the Emeia pseudosauteri population in crisis 23,24,25 . Similar to other species of re ies, Emeia pseudosauteri requires stable and high-quality habitats for eggs, larvae and adults and is highly sensitive to environmental changes and disturbances by human activities 21 , making it an excellent environmental indicator species.…”

Predicting the potential suitable distribution area of Emeia pseudosauteri in Zhejiang Province based on the MaxEnt model

“…The annual firefly glow show staged in the local area is as bright and spectacular as a night sky covered with stars, and this light can induce a strong visual impact and emotional response in viewers, attracting a large number of tourists, gradually forming an ecotourism project in the local area with the frefly viewing experience as the main focus, and bringing tangible economic benefits to the people 26 . However, the excessive interference of human activities, domestic sewage, pesticides, night lights, road hardening, and the proliferation of tourists are causing damage and pollution to the existing habitat of E. pseudosauteri in Zhejiang Province, making the survival and reproduction of the species in crisis [27][28][29] . Similar to other species of fireflies, E. pseudosauteri requires stable and high-quality habitats for eggs, larvae and adults and is highly sensitive to environmental changes and disturbances by human activities 25 , making it an excellent environmental indicator species.…”