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 treat...

An integrative study on Mesobuthus rakhshanii (Scorpiones: Buthidae)

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An integrative study on Mesobuthus rakhshanii (Scorpiones: Buthidae)

Abstract

Mesobuthus Vachon, 1950, with 30 described species is widely distributed from the Eastern Mediterranean area to the Eastern Palaearctic. Mesobuthus rakhshanii Barahoei, 2022 is described from the north of Sistan & Baluchestan and southern parts of South Khorasan Provinces. Totally, 213 specimens of M. rakhshanii were collected from the various habitats of these regions during 2021 to 2023. Specimens were studied from morphological, molecular, biological, and ecological point of view. Bayesian inference (BI) analysis based on the COI gene was conducted. Thirty pairs of alive specimens were used for biological study. The maximum entropy model (MaxEnt) was utilized to evaluate the contribution rates of bio-climatic factors and to project suitable habitats for of M. rakhshanii. Unlike other Mesobuthus species, the central median and posterior median carinae of the carapace of M. rakhshanii are not connected. According to the BI, M. rakhshanii forms a sister group with M. navidpouri, indicating that they are the two youngest species within the genus. Mesobuthus mirshamsii was sequenced for the first time and the validity of this species was confirmed. The observed litter size for M. rakhshanii ranged from 22 to 36. Our findings indicate that annual precipitation and the mean temperature of the coldest quarter are the most influential variables affecting the potential distribution of this species. The estimated optimal distribution area for M. rakhshanii is approximately 943,578 km2, representing about 57.25% of Iran's land area. Among the suitable areas, 10.23%, 41.5%, and 5.52% were classified as low, moderate, and high suitability zones, respectively.

Barahoei, H., Madjdzadeh, S.M. & Moeinadini, A. An integrative study on Mesobuthus rakhshanii (Scorpiones: Buthidae). Biologia 81, 112 (2026). https://doi.org/10.1007/s11756-026-02170-z