Fifteen species of jumping spiders (Salticidae) are reported from the Nimba Mountains in Guinea. The results fully support recognition of the Nimba Mountains as a biodiversity hot-spot. Four new genera are established: Gramenca n. gen. (small spiders with a high carapace and female with a very large epigyne), Lamottella n. gen. (medium size spiders with very long first legs and a unique structure of the male copulatory organ), Nimbarus n. gen. (small spiders characterized by the structure of the chelicerae and the male copulatory organ) and Toticoryx n. gen. (small and flat spiders with very distinctive female genitalia). Twelve species are described as new: Cembalea affinis n. sp., Evarcha bakorensis n. sp., E. certa n. sp., E. maculata n. sp., Gramenca prima n. gen., n. sp., Heliophanus heurtaultae n. sp., Lamottella longipes n. gen., n. sp., Langelurillus horrifer n. sp., Nimbarus pratensis n. gen., n. sp., Plexippus fuscus n. sp., Rhene formosa n. sp. and Toticoryx exilis n. gen., n. sp. Habrocestum diversipes Berland & Millot, 1941 is synonymised with H. nigritum Berland & Millot, 1941 and transfered to the genus Langelurillus Próchniewicz, 1994. The Nimba Mountains thus present a very high biodiversity but it is expected that a larger number of endemic species will be identified in this mountain chain with the study of the remaining collections.
Arachnida, Araneae, Salticidae, western Africa, Nimba Mountains, new genera, new species, synonym.