Zacalantica Iredale, 1929 is herein designated to have a priority over the simultaneously proposed Amapileus Iredale, 1929 (new synonymy by first reviser's choice: ICZN Article 24.2). The type species of the former genus, ‘Phenacolepas’ linguaviverrae Melvill & Standen, 1899, and closely resembling 'Phenacolepas' senta Hedley, 1899, have such unique conchological traits as an overhanging posterior apex, a surface sculpture in 'quincunx' order, and a crenulated rim of the aperture (see Hedley, 1899: fig. 1). This enables an unambiguous characterization of Zacalantica in the framework of combined nomenclatural, morphological and molecular phylogenetic studies. Most species in Phenacolepadinae, especially small-to medium-sized ones, belong to this genus . The ventral side of the shell sometimes has a keel along the posterior half of the apertural rim, e.g. in Z. unguiformis (Gould, 1859), but this keel does not bear denticles as in the species of Plesiothyreus. Feminine.