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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Systematic Entomology Laboratory » Research » Publications at this Location » Publication #363875

Research Project: Systematics of Parasitic and Herbivorous Wasps of Agricultural Importance

Location: Systematic Entomology Laboratory

Title: New hymenopteran egg sac associates of the tent-web orbweaver spider, Cyrtophora citricola (Araneae: Araneidae)

item CHUANG, ANGELA - University Of Tennessee
item Gates, Michael
item GRINSTED, LENA - University Of London
item ASKEW, RICHARD - Non ARS Employee
item LEPPANEN, CHRISTY - University Of Tennessee

Submitted to: ZooKeys
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2019
Publication Date: 9/2/2019
Citation: Chuang, A., Gates, M.W., Grinsted, L., Askew, R., Leppanen, C. 2019. New hymenopteran egg sac associates of the tent-web orbweaver spider, Cyrtophora citricola (Araneae: Araneidae). ZooKeys. 874:1-18.

Interpretive Summary: Invasive spiders pose problems from a nuisance to displacing native spiders occupying similar habitat as they expand their ranges. Parasitic wasps can provide control of such spiders by attacking the egg sacs and reducing the negative impact of the spiders. We report here on two such wasps that have traveled with an invasive spider as it spreads globally. New range enxtensions and host associations are reported. Ecologists and biological control experts, especially those concerned with invasive species, will use this information as will entomologists and arachnologists.

Technical Abstract: We report the discovery of two wasp species emerging from the egg sacs of the spider, Cyrtophora citricola (Forskål, 1775), collected from mainland Spain and the Canary Islands. The wasps were identified as Philolema palanichamyi (Narendran, 1984) (Hymenoptera: Eurytomidae) and as part of the Pediobius pyrgo (Walker, 1839) species group (Hymenoptera: Eulophidae). This is the first report of Philolema sp. wasps documented in Europe, and the first documentation of hymenopteran egg predators of C. citricola. The latter finding is particularly relevant, given the multiple invasive populations of C. citricola in the Americas and the Caribbean, where egg sac predation is not known to occur. We describe the rates of parasitism by Ph. palanichamyi from spider egg sacs collected from the southern coast of Spain, and estimate sex ratios and size variation among males and females. Philolema palanichamyi is re-described based on the female holotype and male paratype specimens, with significant range extension noted.