Attack behavior of two wasp species of the Polysphincta genus group (Hymenoptera, Ichneumonidae) on their Orb-Weaver Spider Hosts (Araneae, Araneidae)

Species in the Polysphincta genus group, as far as is known, are exclusively koinobiont ectoparasitoids of spiders. These wasps attack their hosts, inflicting a temporary paralysis, and then lay one egg on the host’s abdomen or prosoma. Parasitoid attack behavior is highly variable among species, in...

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Bibliographic Details
Authors: Kloss, Thiago Gechel, Gonzaga, Marcelo Oliveira, Roxinol, José Augusto Martins, Sperber, Carlos Frankl
Format: article
Status:Published version
Publication Date:2016
Country:Brasil
Institution:Universidade Federal de Viçosa (UFV)
Repository:LOCUS Repositório Institucional da UFV
Language:English
OAI Identifier:oai:locus.ufv.br:123456789/21709
Online Access:http://dx.doi.org/10.1007/s10905-016-9560-6
http://www.locus.ufv.br/handle/123456789/21709
Access Level:Open access
Keyword:Incidence of parasitoids
Orb-webs
Oviposition
Parasitoids
Description
Summary:Species in the Polysphincta genus group, as far as is known, are exclusively koinobiont ectoparasitoids of spiders. These wasps attack their hosts, inflicting a temporary paralysis, and then lay one egg on the host’s abdomen or prosoma. Parasitoid attack behavior is highly variable among species, including occasions where the wasp darts directly and holds the spider, as well as instances involving complex behavioral sequences. In the present study, we describe the attack behavior of Polysphincta sp. nr. purcelli and P. janzeni on Cyclosa fililineata and C. morretes, respectively. All attacks occurred at night. Initially, the female wasp landed on the web hub at the position occupied by the spider, with the spider always escaping from this initial attack. Subsequently, the wasp waited for up to 14 h at the web hub for the spider’s return. The wasp then inserted its ovipositor into the mouth of the spider, after which the spider became paralyzed and remained motionless for at least 30 min. The wasp laid one egg on the surface of the host’s abdomen and remained on the web for at least 1 h thereafter. The lie-in-wait and attack only after the return of the host to the web hub, as well as the permanence of the wasp on the web after the attack are not frequent behaviors described for polysphinctines. Behavioral idiosyncrasies, such as those observed here, are common among polysphinctines, suggesting a high level of specific adaptive matching of polysphinctine parasitoid behavior to their hosts’ biological characteristics.