We present the first account of nesting biology for the Neotropical suboscine genus Laniocera by describing the nest and eggs of the Cinereous Mourner (L. hypopyrra) based on observations made in the Peruvian Amazon during 2001. The cup-shaped nest was in mature floodplain forest among the branches of an epiphytic fern in a small tree 1.8 m above the ground, and contained two buffy eggs with chocolate brown blotches and spots. These observations demonstrate that Laniocera is not a cavity nester, supporting its removal from the myiarchine flycatchers and previous suggestions of a close relationship to the genus Schiffornis.