Arachnologische Mitteilungen 55

Effect of spider web design on wasp parasite 33 3e). It then returned gradually to the starting point at the top of the cocoon, as it continued connecting more threads on the way up. The larva required ca . 20 h to construct its cocoon, which had a yellowish-white colour that darkened to orange- yellow over the next two days. Spider behaviour. We did not notice any change in the spi- der behaviour during the first larval stage and most of the second stage. It was only during the last night of the second stage that the larva induced the spider to construct a sparse tangle, in the case where the spider and its larva were removed from the web. However, when the spider remained in its web, the last-instar larva only attached some threads to the centre of the hub of the orbicular web to secure the cocoon. Discussion Our observations support the hypothesis that the structure and design of normal webs of host spiders of koinobiont pa- rasitoids in the Polysphincta genus group affect the designs of cocoon webs. The orb web of K. cyrtophoroides is a strong, long-lasting structure constructed of dry threads that remain undamaged for many days, even after the spider abandons the web (GB unpubl. data).The dense tangle above and below the dense orb-web gives strong support to the entire structure as in the webs of the sister genera, Cyrtophora and Manogea (Lu- bin 1974, Sobczak et al. 2009). The intact natural web of K. cyrtophoroides therefore gives enough support and protection from predation and environmental conditions to the H. heidy- ae cocoon (Eberhard 2000,Weng & Barrantes 2007, Sobczak et al. 2009, Korenko 2017). It has been proposed that inhibition of adhesive spiral production in cocoon webs could save spider biomass for the larva wasp to ingest (Eberhard 2010a, Korenko et al. 2018). In K. cyrtophoroides silk investment in the cocoon web is mi- nimum (if any) so that the larva has a larger proportion of the spider’s biomass for development, relative to other spe- Fig. 3: Different phases of cocoon construction. a. Third instar larva removing the spider’s carcass at the hub of the orb web. b. Beginning of cocoon con- struction around the rear section of the larva. c. Larva constructing the upper section of the cocoon. d. Larva attaching silk threads to the cocoon web. e. Larva adding more threads to the lower section of the cocoon. f. Unfinished cocoon after several hours of construction