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1 Spiders constitute an extensive and diverse branch of the phylum Arthropoda. 2Whereas the genomes of four web-weaver spider species and a single cave-living 3 spider have been determined, similar studies have not been reported previously for a 4 wandering spider. The pond wolf spider, Pardosa pseudoannulata, is a wandering 5 hunter that immobilizes prey using venom rather than a web. It is also an important 6 predator against a range of agriculturally important insect pests. The increasing 7 interest in its wandering lifestyle and in the potential of spider venom as a tool for 8 pest control have prompted a detailed study on this wandering spider species. We 9 have generated a high-quality genome sequence of P. pseudoannulata and analysed 10 genes associated with the production of silk and venom toxins. Sequencing reveals 11 that P. pseudoannulata has a large genome of 4.26 Gb. The presence of only 16 12 spidroin genes and four types of silk glands is consistent with the moderate use of silk 13 and the lack of a prey-catching web. A large number of genes encode neurotoxins and 14 there is evidence that the majority are highly selective for invertebrates. Comparison 15 between spider species reveals a correlation between spider neurotoxin selectivity for 16 target organisms and spider prosoma size, suggesting a possible coevolution of these 17 two features. The genome data provides valuable insights into the biology of P. 18 pseudoannulata and its potential role as a natural enemy in pest control. 19

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Vitellogenin receptor (VgR) is crucial for vitellogenin (Vg) uptake by oocytes. VgR is less known in Arachnida, especially in spiders. Different from only one VgR in an arthropod species, two VgRs, VgR‐1 and VgR‐2, were found in the pond wolf spider, Pardosa pseudoannulata. Both VgRs had the typical domains of the low‐density lipoprotein receptor family except for the absence of the ligand‐binding domain 1 in VgR‐2. Spatiotemporal expression profiles showed that two VgR genes were consistently highly expressed in females and their ovaries, but VgR‐1 was 48‐fold that of VgR‐2 in ovaries. The transcriptional level of VgR‐1 was significantly downregulated by RNAi, but it did not work for VgR‐2 although several trials were performed. Vg‐1 and Vg‐2 might be the ligands of VgR‐1 because their expressions were also decreased in the dsVgR‐1‐treated females. Silencing VgR‐1 prolonged the pre‐oviposition period by 56 h. The expression of VgRs and Vgs were upregulated by juvenile hormones (JHs), which suggested that JHs were the essential factors to vitellogenesis in the spider. The present study revealed the importance of VgR‐1 in the spider oviposition, which will improve the understanding on VgR physiological functions in spiders.