RESUMO
Samples of Nicoletiidae (order Zygentoma = Thysanura s. str.) collected in two localities from Puerto Rico belonging to the genus Anelpistina Silvestri, 1905 are studied. One of them, collected in the same cave where A. puertoricensis Espinasa and Baker Alpheis, 2003 was found, allows for the description of the female of this species, together with some additional information on the variability and postembryonic development of this troglobitic insect. The second consists of specimens collected in litter of the islet of Palominos, near the northeastern coast of the main island of Puerto Rico; these specimens are identified as a new species. This species, named Anelpistina naarae sp. nov., is described and compared with related species. A genetic analysis of its DNA and 16S rRNA compared with the available data of the remaining species points to the chronology of the lineages of Anelpistina in this island and their relationships with continental species of the genus.