The excretory system of Hutchinsoniella macracantha (Crustacea, Cephalocarida)
The primary excretory organ of adult Hutchinsoniella macracantha is the maxillary gland, which is located laterally in the posterior portion of the cephalon. It consists of an end sac and a tubule which is divided into proximal and distal sections. The end sac is composed of podocytes filled with endocytotic vesicles which grade in size upward to a large residual body. A large valve controls the o