Crystalline Butterflies - these creatures possess a silicon-based biochemistry and are composed primarily of
 calcium and silicate compounds. The body of a creature is mostly calcite, with some of the internal organs composed
 of a material similar to quartz with piezoelectric properties. This silicate impurity adds rigidity to the creature.
 When any adult instance of SCP-553 suffers significant damage, it produces a unique sonar signature which alerts all
  other nearby adults to the presence of danger. Adults will swarm the perceived source of danger and proceed to
  attack it by attempting to slice it with their wings.