Work found, with species-group names introduced therein:
Díaz, J. M. and L. E. Velásquez. 1987. A new species of Pachybathron from the Caribbean coast of Colombia (Prosobranchia: Marginellidae). Archiv für Molluskenkunde 117 217-221. [Stated date: 12 Jun 1987.] Pachybathron tayrona