Definitions

Nomenclature of isopod cephalon (A). Examples of isopod mouth appendages: Idoteidae (B, C, F, H); Cirolanidae (D, E, G, I). [Wetzer et al. 1997]
(Taxon-specific: Order Isopoda) A sternal plate arising between the bases of the antennae and probably homologous to the epistome of their arthropods; in many isopods the frontal lamina may extend anteriorly to be visible in the dorsal aspect; in many Valvifera the upper and lower regions of this structure may be separately elevated and visible in the dorsal aspect as two distinct structure (frontal lamina 1 and frontal lamina 2). [Wetzer et al. 1997]
(Taxon-specific: Order Isopoda) Plate-like structure anterior to mouth-parts, usually situated between antennae, (pentagonal, quadrate, spiniform, triangular). [Stachowitsch, 1992]
Schematic representation of an isopod illustrating morphological terms. [Kensley and Schotte, 1989]
(Taxon-specific: Order Isopoda) Platelike structure of the cephalon immediately anterior to, and sometimes fused with, clypeus. [Kensley and Schotte, 1989]