A pseudoscorpion clinging to a cave salamander: phoresy or failed predation?

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  A pseudoscorpion clinging to a cave salamander: phoresy or failed predation? Abstract Pseudoscorpions are well known for phoretic associations with arthropods, but interactions with amphibians are rarely documented. Here we report a pseudoscorpion attached to the left palpebral region of an adult male Italian cave salamander, Speleomantes italicus , observed during a visual survey in a karst cave in Tuscany, Italy. The pseudoscorpion, assigned on the basis of visible morphology and locality to Chthonius cf. elongatus , was grasping a minute cutaneous fold on the lower margin of the left upper eyelid with one chela while the salamander moved slowly over the rock surface. No handling was performed and the initial contact between the two animals was not observed. The event therefore cannot be interpreted unambiguously, but may represent opportunistic phoresy or defensive attachment following a failed predation attempt. To our knowledge, this is the first published observation of a ...

Cloning and functional analysis of vitellogenin receptor gene PastVgR1 regulates reproduction in Pardosa astrigera (Araneae: Lycosidae): a potential target for mass rearing of predatory spiders in pest management

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Cloning and functional analysis of vitellogenin receptor gene PastVgR1 regulates reproduction in Pardosa astrigera (Araneae: Lycosidae): a potential target for mass rearing of predatory spiders in pest management

Abstract

Spiders are major predatory natural enemies in agricultural and forest ecosystems and play an important role in pest control. The vitellogenin receptor (VgR) mediates the endocytosis of vitellogenin (Vg) into developing oocytes, providing essential nutrients for embryogenesis and playing a critical role in insect reproductive processes. In this study, A VgR gene was cloned from adult female Pardosa astrigera (L. Koch) and designated as PastVgR1. The open reading frame of PastVgR1 is 5,337 bp in length and encodes a protein of 1,779 amino acids, with a predicted molecular weight of 197.8 kDa. Sequence analysis revealed that the PastVgR1 protein possesses an N-terminal signal peptide consisting of the first 17 amino acid residues and contains conserved domains characteristic of the LDLR superfamily. RT-qPCR analysis showed that PastVgR1 expression was highly specific to the ovaries, with the highest levels in virgin females. RNA interference (RNAi)-mediated silencing of PastVgR1 significantly prolonged the pre-oviposition period, caused ovarian atrophy and oocyte dispersion, reduced both the number of eggs laid per female and the hatching rate, and delayed ovarian development. In summary, PastVgR1 represents a promising molecular target for enhancing the mass rearing of predatory spiders used in biological pest management. Optimizing the large-scale production of these natural enemies could lower the cost of biological control and ultimately support the development of sustainable, green agriculture.

Shen, F., Zhai, S., Wang, X., Jin, X., Cui, C., Ren, B., Zhang, X., Ma, M., Rieger, M. A., Li, X., & Li, R. Cloning and functional analysis of vitellogenin receptor gene PastVgR1 regulates reproduction in Pardosa astrigera (Araneae: Lycosidae): A potential target for mass rearing of predatory spiders in pest management. Journal of Economic Entomology. https://doi.org/10.1093/jee/toag092