Species Composition and Diurnal Activity Rhythm of Tabanids (Diptera: Tabanidae) at the Ivindo National Park and Its Environs

An entomological prospection to show the species composition and diurnal activity of tabanids was carried out using 15 Vavoua traps, during the rainy season (25th Sept-5th Oct and 21st Oct-9th Nov 2018), in the secondary forest [Ivindo National Park (INP)] and Village-Town sites in and around the biosphere reserve Ipassa-IRET Makokou in Gabon. In total, 839 tabanids were caught with 747 recorded at INP and regrouped under 11 species of the genus Tabanus [T. taeniola (57.76%),               T. ricardae (26.32%), T. par (5.54%), T. ruficrus (3.74%), T. socius (3.74%), T. disjunctus (2.49%), T. marmorosus (0.28%) and T. obscurehirtus (0.14%)]. However, two species of the genus Chrysops [C. dimidiatus (70.83%) and C. silaceus (29.17%)] and one species of the genus Haematopota [H. pluvialis (100%)] were only identified at INP. While in the Village-Town sites, 92 tabanids were caught and regrouped under five species of the genus Tabanus [T. ruficrus (14.13%), T. taeniola (9.78%), T. ricardae (73.91%), T. par (1.09%), and T. marmorosus (1.09%)]. Tabanids were more abundant in the forest (7.12 tabanid/trap/day) as compared to the Village-Town (0.77 t/t/d) with a statistically significant difference (P<0.05). At INP, tabanids showed a unimodal activity pattern with peak attained between 12-14H and in the anthropized milieu (14-16H) and dominated by females.