An Architect Cicada in Brazilian Rainforest: Guyalna chlorogena (Walker)

To study the noteworthy nest building behavior of the nymph of the Brazilian Rainforest cicada Guyalna chlorogena (Walker) during the last year of its underground life, we monitored a large number of edifices, consisting of a vertical well (up to 1 m deep) with a turret (20 to 40 cm tall) on top, and we also performed experiments. We have shown that the buildings are occupied by a single nymph, male or female, which increases the height of its turret each night by about 3 cm, during a short active growing phase. The nymph softens and reshapes the apex by pushing upwards a lump of freshly mixed soaked clay, without any opening present, i. e., without ever exposing itself to the outside. We also established that the nymph is very active once its building is achieved. For example, it restores the height of the turret to its original value when shortening and opens the top of its building in case of variation of environmental parameters. Finally, we have shown how the nymph opens its edifice to reach the outside for molting into an adult stage (imago). With this work, we contributed to a better understanding of the nesting behavior of Amazon cicadas.