New insights into coevolution between plants and their cryptic pollinators

Obligate pollination mutualisms are ideal models for studying coevolution. Long thought to be rare, a growing number of examples have been discovered and reported in recent decades. This review discusses two pollination mutualisms characterised by reciprocal adaptations between cryptic insects and their host plants: Asian Schisandraceae-resin midges and leafflower (Phyllanthaceae)-leafflower moths. Both of these systems involve tiny, nocturnal insects, which as adults pollinate their host plants but as larvae feed on the same hosts. We highlight the potential for these systems to shed light on mutualism evolution and geographic dynamics of coevolution. We conclude by emphasising the economic and cultural importance of the Schisandraceae-midge mutualism on food and medicine, and recommend future research in the genomics, coadaptation, and coevolution.