Give the name of the excretory organ present in the following animals

Give the name of the excretory organ present in the following animals.
(i) Rotifers (ii) Cockroaches
(iii) Lancelets (iv) Amphioxus

(i) Rotifers — Flame cells
(ii) Cockroaches — Malpighian tubules
(iii) Lancelets — Protonephridia
(iv) Amphioxus — Nephridium