The main excretory organ of prawn is

• green gland

• flame cell

• Malphigian tubule

• nephridia

A.

green gland

The main excretory organs of prawn are paired green glands. They are located within the second antennae, which are the second pair of appendages, attached to the anterior part of the body. Each green gland consists of on endsac, labyrinth and a bladder.

Flame cell is a specialized excretory cell found in the simplest freshwater invertebrates, including flatworms, rotifers and nemerteans. It functions like a kidney, removing wate material.

The Malphigian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids and tardigrades. It consist of branching tubules extending from the alimentary canal that absorbs solutes, water and wates from surrounding hemolymph.

Nephridium is an invertebrate organ which occurs in pairs and performs a function similar to the vertebrate kidney.