General Characteristics and Classification of Porifera
General Characteristics Classification Phylum Porifera has been divided into three class which are- Class1- Calcarea Class2- Hexactinellida Class3- Demospongea CLASS 1: CALCAREA • These are small sized calcareous sponges (10cm in height). • Solitary or colonial. • Body cylindrical or vase like in shape. • Skeleton formed of calcareous spicules which may be one, three, or four rayed. • All are marine animals. • Body organisation may be asconoid, Syconoid or lenconoid type. ORDER-1 HOMOCOELA • Asconoid sponges with radially-symmetrical and cylindrical body. • Body wall thin and unfolded; choanocytes line the spongocoel. • Often colonial. Example- Leucosolenia, Clathrina ORDER-2 HETEROCOELA • Syconoid and leuconoid sponges with thin walled vase shaped body. • Choanocytes are found in radial canals or infla...