Tricholeiperia trinidadensis n. sp. from the small intestine of Natalus tumidirostris haymani and Natalus sp. in the Tamana caves, Trinidad, West Indies is described and illustrated. The species is separated from the other five species in the genus, namely, T. leiperi Travassos, 1935, T. proencai Travassos, 1937, T. carnegiensis Chitwood, 1938, T. pearsei Chitwood, 1938 and T. poeyi Barus & Valle, 1967. It is characterised by (i) the morphology of the cephalic vesicle which is umbrella shaped, asymmetrical and almost undivided, (ii) the shape and size of the alate, filiform spicules which have a short external alate branch near the pointed distal tip, (iii) the presence of a vulvar flap, (iv) the presence of a median notch on the posterior bursal margin, (v) the dorsal ray which divides distally each branch dividing again into three branches, and (vi) the lateral rays which have a common stem, the antero-lateral and medio-lateral, fused for most of their length, diverging distally and the shorter postero-lateral arising near the base of the other lateral rays.