Nest building by a neotropical social wasp using Cecropia trichomes as main construction material (Hymenoptera,Vespidae, Polistinae)

Nest architecture is such a splendid product of social wasp behavior, there being a large diversity of nest types in the Neotropical fauna. Charterginus is a small wasp genus with six species recorded from Honduras through South America, and one species C. fulvus is notable for normally making nests with a very peculiar star shape. Few behavioral traits of this genus have been described, an exception being a record of cleptobiosis between Charterginus species and Azteca ants on Cecropia trees in Amazonia and Central America. Here we describe behavioral traits of C. fulvus related to the construction process of the nest envelope and the materials used, discussing the apparent dependency of this wasp species on resources provided by Cecropia trees. Experimental induction of reconstruction of the envelope resulted in a different oval regular shape, without the characteristic hollow points. Evidence is also presented of the use by this wasp of lichen components to make the white spots typically seen on nests.