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Spider venom is a natural source of diverse biomolecules, but due to technical limitations, only a small fraction has been studied. With the advancement of omics technologies, research on spider venom has broadened, greatly promoting systematic studies of spider venom. Agelena limbata is a common spider found in vegetation, known for constructing funnel-shaped webs, and feeding on insects such as Diptera and Homoptera. However, due to its small size and the difficulty in obtaining venom, the composition of Agelena limbata venom has never been studied. In this study, a transcriptomics approach was used to analyze the toxin components in the venom of Agelena limbata, resulting in the identification of 28 novel toxin-like sequences and 24 peptidases. Based on sequence similarity and differences in cysteine motifs, the 28-novel toxin-like sequences were classified into 10 superfamilies. According to the results annotated in the database, the 24 peptidases were divided into six distinct families, with the serine protease family being the most common. A phylogenetic tree was constructed using the toxin-like sequences of Agelena limbata along with Psechrus triangulus and Hippasa lycosina. An analysis of the structural domains and motifs of Agelena limbata was also conducted. The results indicated that Agelena limbata is more distantly related to the other two species of funnel-web spiders, and that the toxin superfamily IX has a unique function compared to the other superfamilies. This study reveals the components of the Agelena limbata venom, deepening our understanding of it, and through bioinformatics analysis, has identified unique functions of the toxin superfamilies, providing a scientific basis for the development of bioactive drugs in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Macrothelidae is a family of mygalomorph spiders containing the extant genera Macrothele and Vacrothele. China is an important center of diversity for Macrothele with 65 % of the known species occurring there. Previous work on Macrothele was able to uncover several important toxin compounds including Raventoxin which may have applications in biomedicine and agricultural chemistry. Despite the importance of Macrothele spiders, high-quality reference genomes are still lacking, which hinders our understanding and application of the toxin compounds. In this study, we assembled the genome of the Macrothele yani to help fill gaps in our understanding of toxin biology in this lineage of spiders to encourage the future study and applications of these compounds. The final assembled genome was 6.79 Gb in total length, had a contig N50 of 21.44 Mb, and scaffold N50 of 156.16 Mb. Hi-C scaffolding assigned 98.19 % of the genome to 46 pseudo-chromosomes with a BUSCO score of 95.7 % for the core eukaryotic gene set. The assembled genome was found to contain 75.62 % repetitive DNA and a total of 39,687 protein-coding genes were annotated making it the spider genome with highest number of genes. Through integrated analysis of venom gland transcriptomics and venom proteomics, a total of 194 venom toxins were identified, including 38 disulfide-rich peptide neurotoxins, among which 12 were ICK knottin peptides. In summary, we present the first high-quality genome assembly at the chromosomal level for any Macrothelidae spider, filling an important gap in our knowledge of these spiders. Such high-quality genomic data will be invaluable as a reference in resolving Araneae spider phylogenies and in screening different spider species for novel compounds applicable to numerous medical and agricultural applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Here male specimens of the trapdoor spider family Halonoproctidae collected from Yunnan Province, China are diagnosed and described as new to science based on their genital morphology. Specimens are identified as two new species of Conothele Thorell, 1878: C. cangshan sp. nov. and C. deqin sp. nov.

Species delimitation is critical to our understanding of evolution, biodiversity, and conservation. However, delimiting species boundaries can be challenging, especially when intraspecific divergence is high (and interspecific divergence is low), and gene flow and incomplete lineage sorting are present. Mygalomorph spiders have become models for examining a variety of evolutionary and biogeographical questions. However, their extreme morphological homogeneity and high genetic structuring make delimiting mygalomorph species especially challenging. Integrative approaches to species delimitation, which combine multiple lines of evidence, have been used to infer the limits of many mygalomorph groups in an independent and reproducible way. Yet molecular species delimitation and phylogenetic relationships of the purseweb spider family Atypidae remain scarce. In this study, we explored the phylogeny and species delimitation of Calommata spiders from southern China using data sets including three mitochondrial (COI, 16S, and 12S) and two nuclear (28S, H3) markers. Our phylogenetic analyses yielded a well‐supported clade containing all southern Chinese Calommata and a sister relationship between C. signata and three new species within it. Based on the single‐locus and multilocus species delimitation analyses, we delimited four Calommata species from southern China: one known species (C. signata) and three new species (C. yuanjiangica sp. n., C. hangzhica sp. n. and C. jinggangica sp. n.). This study thus provides a framework for determining the limits of C. signata sensu lato species and calls for further study of systematics and evolutionary relationships within Calommata and other atypid lineages. [ABSTRACT FROM AUTHOR]

Five species of the genus Opopaea Simon, 1892 from southern China are recognised, including four new species: Opopaea mangun Tong & Li, sp. nov., Opopaea taibao Tong & Yang, sp. nov., Opopaea wenshan Tong & Zhang, sp. nov. and Opopaea yuhuang Tong & Li, sp. nov. from Yunnan and one newly-recorded species: Opopaea foveolata Roewer, 1963 from Hainan. Detailed diagnoses, descriptions and photomicroscopy images of new species are provided, based on specimens of both sexes. A key to species of the genus Opopaea from China is provided. [ABSTRACT FROM AUTHOR]

• Eight spiders belonging to five diverse genera and four varying families are studied. • Venom glands are a practical alternative to venom for Raman research. • Raman spectroscopy is an effective method with good repeatability and stability to study spider venom glands, which can provide a preliminary classification for the eight spiders. • The active ingredients in the venom glands of all eight spiders contain carotenoids. Spider venom has high research value for use as an insecticide and drug, but its extraction is expensive and complicated. In this paper, Raman microspectroscopy was used to determine the secondary structure of the proteins, which are the active ingredients in venoms, and the venoms were obtained from eight spiders: Hippasa lycosina, Lycosa grahami, Lycosa wangi, Lycosa yunnanensis, Heteropoda venatoria, Psechrus ghecuanus, Macrothele yani and Macrothele yunnanica. The results indicate that venom glands are the preferred substitute for venom for research. Second, the eight glands have similar strongest Raman peaks, but there are partial differences in the weaker peaks and relative intensity ratios, and the differences can give a preliminary classification for the eight spiders. Third, Raman spectroscopy is an effective method with good repeatability and stability to study spider venom glands. [Display omitted] [ABSTRACT FROM AUTHOR]