Work found, with species-group names introduced therein:
Leal, J. H. and D. R. Moore. 1993.Thala esperanza, a new Costellariidae (Mollusca: Gastropoda) from northern Puerto Rico. Nautilus 107 58-62. [Stated date: 28 Jul 1993.] Thala esperanza, see Mitromica esperanza (Leal & Moore, 1993)