- Arachnological Society of Japan
- Acta Arachnologica (ISSN:00015202)
- vol.68, no.2, pp.77-80, 2019-12-20 (Released:2019-12-29)
Parasitism by the ichneumonid ectoparasitoid, Brachyzapus nikkoensis, on the agelenid spider, Allagelena opulenta is recorded for the second time with the first voucher specimen. The attacked host was an adult in contrast to the exclusive utilization of juveniles of the main host, Agelena silvatica. All published records of parasitism upon Agelena silvatica are from spring to early summer, and therefore this finding of parasitism in the end of September, would be consistent with B. nikkoensis shifting its hosts in accordance with their body size, seasonal prevalence and their availability, as previously suggested.