Fantastic feasts and where to find them: mosquito (Diptera: Culicidae) sugar feeding and survivorship on endemic flowers of arid scrublands

Mosquitoes, like many other insects, are dependent on plant-derived nutrients as adults. Arid lands in particular create a challenge for mosquitoes to find resources consistently. In the United States, the arid, high elevation floodplains around the Great Salt Lake present a rich environment where salt desert shrublands meet alkaline freshwater wetlands, while plant communities contain a diversity of native and invasive flower species. We investigated survivorship on 15 flowering plants representing the common ephemeral wildflowers found through the aforementioned habitats using local Culex pipiens (L.) under laboratory conditions. Four native angiosperm species, Cleome serrulata Pursh (Brassicales: Cleomaceae), Asclepias incarnata L. (Gentianales: Apocynaceae), Asclepias speciosa Torrey, and Verbena hastata L. (Lamiales:Verbenaceae) had the highest mosquito mean percent survival in 10-day assays. Mosquito survival was significantly better on native flowers than on non-native flowers. Endemic mosquitoes in the field were also sampled for frequency of sugar feeding at six sites across 11 weeks. Flower phenology data of the aforementioned four flowers with highest mosquito mean percent survival were taken from iNaturalist and compared to the abundance of sugar-fed mosquitoes from the wild. Flower phenology and sugar-fed mosquito abundance followed the same trends, with increased flower sightings co-occurring with increased sugar feeding. The short-lived blooming intervals in the arid landscape result in time periods when both flower sightings and sugar feeding in mosquitoes are low, highlighting elevated risks to exposure and malnutrition for wild populations. Sustainable research and management of mosquitoes require answers to basic biological and ecological questions such as flower dependence and resource scarcity in the field.