The Neotropical beetle Cephaloleia fenestrata is a specialist herbivore on Pleiostachya pruinosa (Marantaceae) in upland and flood zone habitat of lowland tropical wet forest in Costa Rica. Cephaloleia fenestrata spends its entire life cycle on P. pruinosa, feeding primarily in rolled young leaves as adults, feeding in the concavity of leaf petioles as larvae, and laying eggs and pupating on the leaf petioles. Egg development time is about average for Chrysomelidae, approximately ten days. Cephaloleia fenestrata larvae, like other rolled leaf hispines, have an extremely long development period (94 d) consisting of only two instars (compared to a range of three to six in other Chrysomelidae). The 30-day pupal stage is also long, but within the range of that observed in other Chrysomelidae. Adults live an average of six weeks. The generation time for C. fenestrata is thus approximately six months. Male C. fenestrata lived longer and had a higher capture probability than females. There was no difference between males and females in the movement probabilities between upland and flood zone habitat. Rolled P. pruinosa leaves are both ephemeral (available to the beetles for approximately two days) and somewhat rare (1 in ca 15 ramets has a rolled leaf). Adults must move from leaf to leaf ca 36 times during their average adult life span. Still, C. fenestrata adults demonstrate high site fidelity.