New locality records and future habitat suitability of Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt

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  New locality records and future habitat suitability of Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt Abstract This study reports new locality records from Iran and a climate-based habitat suitability assessment for Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt. We document new specimens from Sistan and Baluchestan Province, Iran, with an updated distribution map and illustrations, and we model the species' potential distribution across south-eastern Iran and adjacent parts of Afghanistan and Pakistan. Habitat suitability was associated mainly with precipitation seasonality, precipitation of the wettest month, precipitation of the driest month, and slope. In an arid setting these rainfall variables are unlikely to indicate a need for moist habitat; they more plausibly track seasonal productivity and the terrain features that provide shelter. Present-day suitable areas...

Sublethal effects of matrine and azadirachtin on the wolf spider Pardosa laura: no impairment of growth but marked suppression of reproduction

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Sublethal effects of matrine and azadirachtin on the wolf spider Pardosa laura: no impairment of growth but marked suppression of reproduction

BACKGROUND

Plant-derived pesticides (PDPs) are increasingly promoted as ‘eco-friendly’ alternatives to agrochemicals because of their low vertebrate toxicity, yet their safety for non-target arthropod natural enemies is rarely tested, especially the enrichment effect via trophic transfer.

RESULTS

We cultured fruit flies using media supplemented with two widely applied Chinese PDPs in tea plantations, matrine or azadirachtin, under commercial concentration, which were fed to newly emerged spiderlings of wolf spider Pardosa laura (Araneae: Lycosidae) throughout their entire life cycle. We examined the effect of these two PDPs on their survival, developmental parameters and reproduction. The results showed that developmental traits remained unaffected, but both PDPs markedly suppressed male mating success and female fecundity. Histological examination of paraffin sections revealed markedly impaired ovarian maturation. Microbiome profiling indicated that pesticide exposure disrupted ovarian microbial communities, with azadirachtin exerting the strongest effect, whereas gut and testicular communities remained largely unchanged. Transcriptomic analysis of ovaries showed significant enrichment of pathways related to ovarian development. Ten representative differentially expressed genes (DEGs) within these pathways were selected and validated by RT-qPCR.

CONCLUSION

PDPs may not compromise the development of spiders in the first generation, yet they can severely affect reproduction of the spiders, thereby precipitating substantial declines in population size of future generations. This result challenges the conventional wisdom of botanical pesticides, inspiring re-consideration of their rational use in integrated pest management. © 2025 Society of Chemical Industry.


Ma, Y., Yan, H., Abukhader, O. S., Li, D., & Zhang, S. Sublethal effects of matrine and azadirachtin on the wolf spider Pardosa laura: No impairment of growth but marked suppression of reproduction. Pest Management Science. https://doi.org/10.1002/ps.70347