One more new species of Chaerilobuthus Lourenço & beigel, 2011 (Scorpiones: Chaerilobuthidae) from Early Cretaceous Burmite

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  One more new species of Chaerilobuthus Lourenço & beigel, 2011 (Scorpiones: Chaerilobuthidae) from Early Cretaceous Burmite Abstract . – The genus Chaerilobuthus is probably the most speciose group among those found in Burmite. In some recent publications most aspects concerning the family Chaerilobuthidae Lourenço & Beigel, 2011 and the genera composing it were precisely discussed; consequently, no further comments will be provided in this contribution. Only one more new species belonging to the genus Chaerilobuthus is described. Chaerilobuthus franzschmidti Lourenço sp . n ., represents the 16th species to be described for this genus confirming therefore the strong speciose characteristic of the group. The new species shows some marked morphological differences when compared to the previous known species, attesting the existence of a major variability within Chaerilobuthus . Lourenço W. R. & Velten J., 2026. – Une nouvelle espèce pour le genre Chaerilobuthus Lou...

The neonicotinoid imidacloprid impairs the predatory performance and functional response of the jumping spider Helpis minitabunda (Araneae, Salticidae)

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The neonicotinoid imidacloprid impairs the predatory performance and functional response of the jumping spider Helpis minitabunda (Araneae, Salticidae)

Abstract

The neonicotinoid imidacloprid can cause lethal and sublethal effects in non-target organisms, including impaired behavior, reduced fertility, disrupted locomotion, and reduced predatory performance in arthropods. Spiders are among the most abundant arthropod predators in terrestrial ecosystems, including agricultural ecosystems, yet the effects of neonicotinoids on the predatory function of jumping spiders remain poorly understood. The functional response of a predator describes how predation rates change with prey density and is key to understanding predator–prey dynamics. We tested whether acute exposure to a commercial formulation of imidacloprid at field-recommended concentrations alters the functional response of the Aussie bronze jumping spider, Helpis minitabunda (L. Koch, 1880). We compared the predation of treated (imidacloprid) and control (distilled water) spiders across 5 prey densities over a 9-h observation period. Both treated and control spiders exhibited a Type II functional response. However, treated spiders showed more than double the handling time compared to controls, with no difference in attack rate, indicating impaired prey processing efficiency rather than reduced prey detection ability. Overall, treated spiders killed fewer prey than control spiders, and the mean realized predation rate at the highest prey density was more than halved. Control spiders killed more prey as prey density increased over the early observation periods (up to 5 h), whereas treated spiders did not. Our findings demonstrate that acute exposure to field-relevant concentrations of imidacloprid impairs the predatory performance of the jumping spider H. minitabunda, which has potential implications for natural pest suppression by spiders in ecosystems where neonicotinoids are applied.

Reshnu Rajan-Sheela, Anne Wignall, The neonicotinoid imidacloprid impairs the predatory performance and functional response of the jumping spider Helpis minitabunda (Araneae, Salticidae), Journal of Economic Entomology, 2026;, toag243, https://doi.org/10.1093/jee/toag243