Tropical Dry Forests (TDF) are one of the most threatened biomes in the Neotropics. However, these host a great variety of species and a high number of endemic plants and animals. It has been documented that 61.7% of the TDF flora is self-incompatible and requires entomophilous pollination, with bees (Hymenoptera: Apoidea) pollinating more than half of TDF plants. Despite this, little is known of the diversity and ecology of these crucial pollinators for TDF. In this study, we present the first overview of bees from TDF based on 44 published studies and ongoing field surveys. Neotropical TDF host 622 species of bees representing five families, corresponding to 12.44% of the total species of bees recorded for the Neotropics. Apidae is the richest family, with 360 identified species, while Andrenidae is the least diverse with only 25 identified species. Only 63.2% of the recorded taxa were identified to the species level, with the family Halictidae displaying the lowest percentage of identifiable species (43.5%), all of which highlights the lack of taxonomic knowledge of bees in this biome. Only 17 TDF ecoregions in 10 countries have been surveyed. TDF of Brazil and Mexico have the highest species richness. The lack of taxonomic studies and systematic surveys in most of the Neotropical TDF, particularly in countries like Bolivia and Peru, currently represents the greatest challenge for documenting the true richness of bees in the Neotropical TDF.
