Foldi, I. 1997 Defense strategies in scale insects: phylogenetic inference and evolutionary scenarios (Hemiptera, Coccoidea).. Mémoires du Museum National d'Histoire Naturelle (N.S.) Serie A, Zoologie 173: 203-230.

Notes: The sedentary plant-parasitic habit of scale insects increases their vulnerability to natural enemies and to adverse environmental factors; strategies for defense include 1. construction of protective structures from secretions and/or excretions; 2. behavioral adaptations to exploit host-plant afforded protection; 3. modifications of their life-cycle in response to environmental factors; and 4. modifications of the female body to provide protection for their progeny.