Diversity, Host Plants and Potential Distribution of Edible Saturniid Caterpillars in Kenya

SIMPLE SUMMARY: Edible insects are a traditional food source with economic benefits in sub-Saharan Africa. Caterpillars are the most popular edible insects in this region. We focus on caterpillars in the family Saturniidae. Saturniids are big colorful caterpillars with spines on their bodies, usually found in shrubs and trees. They are rich in proteins, vitamins, and minerals. Despite their economic importance, little is known about their diversity, host plants, distribution, and potential effect of climate change on edible saturniid caterpillars in Africa. The aim of this study is to identify edible saturniids, their host plants, their current distribution and to predict the possible effects of climate change on their distribution. We documented seven species of edible saturniids namely Gonimbrasia zambesina, Gonimbrasia krucki, Bunaea alcinoe, Gonimbrasia cocaulti, Gonimbrasia belina, Gynanisa nigra and Cirina forda. These caterpillars mostly occur twice a year during the rainy seasons and feed on specific host plants. Predictive distribution models revealed that B. alcinoe, and C. forda are mostly found in tropical and sub-tropical regions in Africa. However, climate change could cause a slight decrease in their population by the year 2050. This information will guide conservation efforts and ensure sustainable use of edible saturniid caterpillars as food. ABSTRACT: The promotion of edible insects, including saturniid caterpillars as potential food source is widely gaining momentum. They are adequately rich in nutrients such as proteins, amino acids, fatty acids, and micronutrients. Despite saturniids being a traditional food source with economic benefits, information on their diversity, host plants and their potential distribution in Africa are lacking, which this study seeks to address. Edible saturniids and their host plants were characterized using specific primers (LepF1/LepR1 and 3F_KIM_F/1R_KIM_R, respectively). Maximum entropy (MaxENT) and GARP (genetic algorithm for ruleset production) models were used to characterize the potential distribution of commonly consumed saturniids under current and future climate scenarios. Seven species of saturniids were recorded from 11 host plants in Kenya: Gonimbrasia zambesina, Gonimbrasia krucki, Bunaea alcinoe, Gonimbrasia cocaulti, Gonimbrasia belina, Gynanisa nigra and Cirina forda. Two morphotypes of G. zambesina and B. alcinoe were recorded. These saturniid caterpillars occur twice a year except for G. cocaulti. Predictive models revealed that tropical and subtropical regions were potentially suitable for B. alcinoe and C. forda. The information generated from this study would be important to guide conservation efforts and their sustainable utilization as food in Africa.