Freshwater Sponges of Arunachal Pradesh, India

The sponges are aquatic, sedentary, filter feeding Metazoa with a cellular grade of construction, without organs, mouth or nervous tissue, with a body permeated with pores, canals and chambers and involving a unidirectional water current through the body propelled by random beating of flagella occurring on a single layer of flagellated cells called choanocytes and feed on suspended organic particles. Skeleton - made up mainly of spicules of silica or calcite and spongin fibres laid down around the spicules or parts thereof so that the skeleton held together in a reticulum, a set of plumose fibres, or as dense tracts of spongin and spicules.