Spider venom peptides Ht1a and Gg1a are toxic to honeybee parasite Varroa destructor by topical application

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  Spider venom peptides Ht1a and Gg1a are toxic to honeybee parasite Varroa destructor by topical application Abstract Global food supply strongly depends on honeybee pollination services, which are threatened by insecticides and pests such as parasitic Varroa destructor mites. Chemical varroacides/acaricides are hampered by resistance development, necessitating the development of sustainable and environmentally friendly alternatives, with arthropod venom peptides being considered promising sources of acaricidal toxins. With only a few acaricidal venom peptides being reported, we performed a systematic topical screening of 50 arthropod venoms against V. destructor , with 78% of the venoms causing 100% mortality after 24 h. Deconvolution of the venoms from the Tasmanian cave spider Hickmania troglodytes and the Giant Japanese funnel-web spider Gigathele gigas led to identification of the varroacidal peptides Ht1a and Gg1a. Topical application of Ht1a and Gg1a reduced varroa mite ...

Disparity among venom components, and morphometrics in Centruroides baergi Hoffmann, 1932, a medically relevant scorpion species from Mexico

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Disparity among venom components, and morphometrics in Centruroides baergi Hoffmann, 1932, a medically relevant scorpion species from Mexico

Abstract

Centruroides baergi is a scorpion species distributed in the biogeographical province of the Balsas Basin in Mexico. Health officials have reported acute envenomation in human populations living on the western side of this scorpion's range, but none in the eastern region. This disparity in toxicity suggested that there may be two distinct species. We used two different approaches, including venom analysis and morphometric specimens from both regions, to test our hypothesis. We performed chromatographic, electrophoretic, and mass spectrometry analysis to identify the known β-toxins involved in the intoxication. The most remarkable finding was the absence of Cb3 β-toxin in the eastern population. Consequently, the LD50 of the eastern population was lower than that of the western population. We analyzed linear and ratio body measurements with parametric and nonparametric statistics to test species limits. These analyses indicated that all putative populations of C. baergi are significantly similar, suggesting that they may represent a single species. Unexpectedly, the population of scorpions in the center of the study area, Suchixtlahuaca, previously identified as C. baergi, showed significant morphological and venom composition differences. We provided empirical evidence of an abrupt change of highly toxic peptides around the 98th meridian that limits populations of Centruroides baergi to the east of Mexico.
Bejarano-Mendoza, F. O., Gómez-Ramírez, I. V., Cortés Guzmán, A. J., Becerril, B., Possani, L. D., Cid Uribe, J. I., & González-Santillán, E. (2025). Disparity among venom components, and morphometrics in Centruroides baergi Hoffmann, 1932, a medically relevant scorpion species from Mexico. Toxicon, 108370. https://doi.org/10.1016/j.toxicon.2025.108370