Crucibulum quiriquinae (Lesson, 1830) is the only species of Crucibulum currently recognized in northern Chile. Recent analysis of three Crucibulum populations obtained in northern Chile demonstrates the existence of morphological, genetic, and reproductive differences among populations. Two populations present in Bahía Tongoy (30°15′S), one inhabiting the shells of the snail Turritella cingulata and the other shells of the pectinid Argopecten purpuratus, showed morphological differences. However, both had planktonic larval development and show low genetic divergence (D=0.002). A third population from Bahía La Herradura (29°58′S), which also inhabits the shells of T. cingulata, did not show morphological differences compared with its counterpart from Bahía Tongoy. However the Bahía La Herradura population had intracapsular development and metamorphosis, and a larger genetic distance (D=0.06) from both Tongoy populations. The results of the reproductive and genetic analyses strongly suggested that the two Tongoy populations, although showing morphological differences, are biologically the same species, Crucibulum quiriquinae, whereas the La Herradura population is a new species.