Olea europaea is the botanical name of the olive. It is a small tree species in the family Oleaceae. The olive tree is an evergreen tree or shrub. It is native to the Mediterranean, Asia and Africa. Various pests and diseases can affect olives. The most important is the olive fruit fly (Dacus oleae or Bactrocera oleae) which lays its eggs in the olive. Also the fungus cycloconium oleaginum and the bacteria Xylella fastidiosa cause damage to the olive tree. Xylella fastidiosa causes the olive quick decline syndrome (OQDS).