Among the many examples of freshwater-terrestrial resource subsidies that have been documented, one of the more unique is the phenomenon of butterflies drinking the tears of basking river turtles and caimans. ‘Lachryphagy’ by butterflies was observed in the field on the yellow-spotted river turtle (Podocnemis unifilis) on the Napo and Tiputini Rivers of Ecuador. Here, we explore this phenomenon using photographs and ancillary data drawn from the citizen-science project iNaturalist to answer questions such as: How many butterfly taxa engage in lachryphagy? How widespread is this phenomenon? Are there butterfly preferences for turtles across sexes, sizes, and basking substrates? We found that butterfly lachryphagy on P. unifilis is common; of the 1,387 research-grade photos of P. unifilis uploaded to iNaturalist, 9% (126) contained evidence of this phenomenon. Butterfly-P. unifilis lachryphagy is also widespread and spans 2,700 km longitudinally and 1,500 km latitudinally. We observed 14 butterfly genera showing evidence of lachryphagy on P. unifilis; Dryas iulia was the most commonly observed species, constituting almost half of the butterflies observed. By far the greatest number of P. unifilis photos were of turtles as they basked on protruding large wood (87%), a finding reflective of the importance of this habitat for basking by P. unifilis, and by extension, for butterfly lachryphagy. While the exact resources provided to butterflies through lachryphagy remain to be determined, candidate substances include: minerals (e.g., sodium), proteins, and trace elements. These results matter because butterflies and other insects that engage in lachryphagy are pollinators of terrestrial plants, including those in the upper rainforest canopy, and butterfly larvae can be important herbivores. While some of these results reflect the biases of the photographers, they nevertheless constitute steps towards understanding a unique type of resource subsidy, one involving a freshwater vertebrate of conservation concern; P. unifilis is IUCN red-listed as ‘vulnerable’. These results highlight the myriad and complex connections that exist between tropical freshwaters and seemingly unconnected ecosystems such as the upper canopy of rainforests.