The last instar larva of Penepodium dubium is described from southeastern Brazil. This is the first description of an immature stage of the genus Penepodium. The larva of P. dubium is similar to those of Podium, but it can be distinguished from the species of this genus by the presence of depressions on the front and clypeus, and lack of brownish blotched areas on the head. The cocoon of Penepo...

Coordinated movement of animals is a spectacular phenomenon that has received much attention. Experimental studies of Mormon crickets and locust nymphs have demonstrated that collective motion can arise from cannibalism that compensates for nutritional deficiencies arising from group living. Grouping into migratory bands confers protection from predators. By radiotracking migrating, Mormon cric...

Stabilimenta are zigzag and spiral designs of seemingly conspicuous silk included at the centers of many spider webs. We examined the association of stabilimenta with the ability of spiders to defend themselves against predatory mud-dauber wasps. We found that Argiope trifasciata (Araneae, Araneidae) were signiŽ cantly more likely to survive attacks by Chalybion caeruleum and Sceliphron caement...

The sting apparatus of aculeate Hymenoptera is derived from the ovipositor and their most prominent apomorphy. In contrast to frequently analysed sclerites apparatus, associated musculature has largely been neglected. this study, we use micro-computed tomography present a detailed description Ampulex compressa (Ampulicidae) Sceliphron destillatorium (Sphecidae). We found that 12 15 muscles corr...