Diversity of flowering insects of Jatropha gossypiifolia L. 1753 (Euphorbiaceae) in Maroua (Far North, Cameroon)

In order to determine the floricultural entomofauna of Jatropha gossypiifolia, flowers were observed in 2022 and 2023 in Maroua (Far North, Cameroon). From July 24 to August 01, 2022 and from July 19 to 29, 2023 in Maroua, 120 floral bouquets (at a rate of 60 bouquets for each year of observation) labeled and left in free pollination were observed, the different species of insects visiting the flowers of J. gossypiifolia, the relative frequency of visits, the food products sought, the daily regularity of the various species of flowering insects and their abundances per flower and per 1000 flowers were determined. In 2022 and 2023, the diversity of flowering insects of J. gossypiifolia was 33 and 23 species of insects respectively in Maroua. Most insects visited the flowers of this plant species for nectar and/or pollen, only Calidea panethiopica visited the blooming flowers and flower buds to suck the sap from the plant. The most common insects were Seladonia sp., Apis mellifera, Lipotriches hylaeooides and Belonogaster juncea with a relative frequency of 30.49%, 19.44%, 7.61% and 5.91% respectively. The peak of activity of all insects was between 12 p.m. and 1 p.m. The abundance was one individual per flower for all insect species. The mean abundance per 1000 flowers was 28.86 in Apis mellifera, 42.21 in Seladonia sp. and 29.99 in Belonogaster juncea. Growers of J. gossypiifolia who wish to control Calidea panaethiopica to avoid the period of activity of other floricultural insects during insecticide treatments.