A.叶条形或细棒状,气囊纺锤形或球形,无刺状突起,固着器须根状B.叶披针形,狭披针形或丝状,全缘或有锯齿,革质,有片状突起C.叶丝状,丛生,革质,固着器须根状D.叶圆形,全缘,气囊椭圆形,固着器盘状E.叶倒卵形或披针形,气囊球形或卵球形,侧枝上有细小刺状突起,固着器盘状