Upswing of collections of horse flies (Diptera, Tabanidae) held at the National Museums of Kenya, Nairobi

History of zoogeographical views and actual distribution of 23 determined species of Tabanidae from three subfamilies, five tribes and 8 genera (Philoliche Wiedemann, 1828 - 4 species; Chrysops Meigen, 1803 - 3; Thaumastocera Grünberg, 1906 - 1; Ancala Enderlein, 1922 - 1; Atylotus Osten-Sacken, 1876 - 1; Tabanus Linnaeus, 1758 - 8; Haematopota Meigen, 1803 - 4; Hippocentrum Austen, 1908 - 1) mainly from Kenya are summarized, using the names of recent African countries. Tabanus sericiventris Loew, 1858 is new for Kenya. Lower taxonomical units as Tabanus insignis f. neavei Austen, 1912 and T. marmorosus ssp. congicola Bequaert, 1930 are discussed. A complete new references to all identified taxa are given.