Papilionoideae :
- Flowers usually zygomorphic.
- Flowers perigynous
- The calyx gamosepalous.
- Corolla papilionaceous.
- Androecium generally dia- delphous.
- Stamen inserted.
Caesalpinioideae :
1.Flowers zygomorphic.
2.Flowers perigynous.
3.The calyx generally polysepalous.
4.Corolla caesalpiniaceous i.e., with ascending imbricate aestivation.
5.Androecium ten or less, free.
6.Stamen inserted.
Mimosoideae :
1.Flowers mostly actinomorphic.
2.Flowers hypogynous.
3.The calyx is gamosepalous or polysepalous.
4.Corolla regular, free/fused with valvate aestivation.
5.Androecium many, generally free but rarely monadelphous.
6.Stamen exserted mostly.