Stepaniuk, K., & Lagowska, B. 2006 Number and arrangement variation of submarginal tubercles in adult females Parthenolecanium corni group (Hemiptera, Coccidae) and its value as a taxonomic character.. Polskie Pismo Entomologiczne 75(2): 293-301.
Notes: Evidence is provided showing that the number and arrangement of dorsal submarginal tubercles are not a reliable character to separate species or subspecies in the genus Parthenolecanium. A morphometric analysis of 756 adult females of P. corni collected from 22 different host plants shows that dorsal tubercles are highly variable in number and arrangement and this character is of little diagnostic value on the species or subspecies levels.