After obtaining fresh material of Opatrillus puertoricellis from Puerto Rico a comparison was done with a large series of 0. armasi. This latter taxon had been previously compared with Marcuzzi's original description, mainly based on his illustration of male genitalia from Jamaica reckoned to be 0. puertoricellsis . Genitalia from O. p. puertoricellsis (from Puerto Rico) and O. armasi, proved to be quite alike. Also morphological characters of the two populations are not very distinct, offering differentiations better considered under sub specific rather than specific level. Therefore, we propose considering 0. armasi Garrido and Gutierrez, 1994, as a subspecies associated with O. puertoricellis Marcuzzi, 1977. Based on the differences shown in the male genitalia of 0. armasi and O. puertoricellsis from Puerto Rico and Jamaica, we consider that the animals from Jamaica are different from Puerto Rico's (0. puertoricellsis), and therefore constitute an undescribed species different from 0. puertoricellsis. Specimens assigned to O. pullus from Cuba and Puerto Rico, do not differ, either morphologically, or in their genitalia, therefore both populations should be treated as members of the same taxon.