Ancient trouble in paradise: Seed beetle predation on coconuts from middle–late Paleocene rainforests of Colombia.

Modern Neotropical rainforests are characterized by the high intensity and host specificity with which insects feed on plants. Previous studies have shown that, during the middle–late Paleocene, the leaves of the early evolving Neotropical rainforests of tropical South America were heavily herbivorized by insects. Yet, less attention has been given to insect damage found on fossil fruits and seeds, despite the host specialization of many disseminule predators in modern forests. Here, we present and describe borings found on a fruit compression fossil of cf. Cocos (coconut) from the middle–late Paleocene Cerrejón Formation (58–60 Ma) of Colombia. We interpret the borings as constructed by palm seed beetles (Chrysomelidae: Bruchinae: Pachymerina) based on size, number, position, plant reaction tissue, and plant host selection. This occurrence provides the earliest record of an ecological interaction between seed beetles and palms, suggesting that this host-specific interaction has been consistently maintained for several tens of millions of years. • A fossil cf. Cocos sp. fruit, from the Cerrejón Formation, evidences insect borings. • The borings are consistent with the feeding behavior of palm bruchines (Pachymerina). • The borings represent the earliest association between palm bruchines and palms. • Palm bruchines and palms have interacted since, at least, the middle-late Paleocene. [ABSTRACT FROM AUTHOR]