A new East Africa genus, Tigrisomyia Kirk-Spriggs gen. n., is described; being apparently restricted to high-elevation Afromontane forests associated with the Malawi Rift and Eastern Arc mountain group of Kenya and Tanzania. A diagnosis of the genus is provided and character states (synapomorphies) distinguishing the genus from other genera in the Curtonotidae are outlined. Four new species are described; and are illustrated using pen and ink drawings and light microscopy, namely T. amnoni Kirk-Spriggs, sp. n. (Malawi, Tanzania and Zambia), T. kinskii Kirk-Spriggs, sp. n. (Malawi), T. rhayaderi Kirk-Spriggs, sp. n. (Kenya and Malawi) and T. scoliosis Kirk-Spriggs, sp. n. (Tanzania); the first-named species being designated as type-species for the genus. An identification key to the four species is provided based on external characters. The distribution of the four species is mapped, indicating that T. rhayaderi sp. n. has a disjunct distribution on the Zomba Plateau (Malawi) and coastal forests of Kenya; T. kinskii sp. n. is apparently restricted to Ntchisi Forest (Malawi), and T. kinskii sp. n. to the Rebeho (Usagara) Mountains in the Eastern Arc group. Tigrisomyia amnoni sp. n. is more widely distributed occurring from the West Usambara Mountains in the north of Tanzania to the Zomba Plateau in the Shire District of southern Malawi (and some intervening relict forests). The historical biogeographical significance of the distribution of the four species is discussed in relation to historical pan-African forest cover in Africa.