Syngenesious stamens are commonly found in :

Asteraceae or Compositae is a large and widespread family of flowering plants. It is commonly referred to as a composite family or sunflower family. In Asteraceae, the stamens are 5 rarely 4; epipetalous (stamens are attached to the petals), syngenesious (anthers are united and filaments are free), forming a tube which encloses style.