It is similar to a constitutional monarchy.
No, Brunei is a sovereign state and a constitutional sultanate. It is ruled by a Sultan who is the head of state with full executive authority under the constitution.
The Sultanate of Muscat and Oman is a Arabian Sultanate.
Sultanate of Damagaram was created in 1731.
Pontianak Sultanate ended in 1950.
Pontianak Sultanate was created in 1771.
Sultanate of Lahej was created in 1728.
Sultanate of Lahej ended in 1967.
Kedah Sultanate was created in 1136.
Johor Sultanate was created in 1528.
Delhi Sultanate was created in 1206.
Malacca Sultanate ended in 1511.