Pilemostoma Desbroches, 1891

Cassida sg. Pilemostoma Desbrochers (1891): 14 (type species: Cassida fastuosa Schaller, 1783, by monotypy); Hincks (1952): 339; Seeno and Wilcox (1982): 177.

Pilemostoma: Spaeth (1914b): 89; Spaeth and Reitter (1926): 20; Borowiec (1999): 314.

Glyphocassis Spaeth, 1914 is a genus very close to Pilemostoma . Both genera have similar body shape and elytral pattern. Glyphocassis is divided into two subgenera: the nominotypical subgenus with one species and Hebdomecosta Spaeth, 1915 with two species. The nominotypical subgenus shares many characters with Pilemostoma: deep antennal grooves, marginalia forming gutter, tarsal claws toothed basally and elongate. It differs in having an elongate prosternal collar with angulate sides (short and without angulation in Pilemostoma); an antennal groove bordered externally by a sharp carina (by an obtuse carina in Pilemostoma) and a marginalia of pronotum and elytra impunctate (punctate in Pilemostoma). Both genera are also separated geographically: Glyphocassis s. str. occurs in S China, NE India, and Indochina, while Pilemostoma is known exclusively from the Palaearctis. Hebdomecosta is Palaearctic like Pilemostoma but differs in simple tarsal claws; short, circular body and impunctate marginalia.

Both genera also have different feeding habits. Glyphocassis feeds exclusively on Convolvulaceae (Kalaichelvan et al. 2004; Lee & Cho 2006) while Pilemostoma is associated with Asteraceae (Brovdij 1983; Sekerka 2006). Based on the characters mentioned above I treat Pilemostoma as an independent genus close to Glyphocassis .