The ant genus Trichomyrmex Mayr, 1865 is revised for the Arabian Peninsula based on the worker caste. Nine species are recognized and descriptions of two new species, T. almosayari sp. nov. and T. shakeri sp. nov. from Riyadh Province, Saudi Arabia, are given. For nomenclatural stability, lectotypes for T. abyssinicus (Forel, 1894a), T. lameerei (Forel, 1902) and T. mayri (Forel, 1902) are designated. A key to species and diagnostic characters of the treated species are presented. New country records are presented for T. abyssinicus (Saudi Arabia), T. destructor (Jerdon, 1851) (Saudi Arabia and the United Arab Emirates) and T. mayri (Qatar). New distributional records for T. destructor and T. mayri for Saudi Arabia are also provided. World and regional species distributions are indicated and distributional maps for nine Arabian species are included. Ecological and biological information is given when known.
Myrmicinae, Palearctic Region, Kingdom of Saudi Arabia, key, new record.