Organisation of the capsule of Macrobiotus pallari and Richtersius coronifer (Tardigrada, Eutardigrada, Parachela)

Organisation of the egg capsule of two species of tardigrades belonging to the family Macrobiotidae, Macrobiotus pallari and Richtersius coronifer, was analysed using light, transmission and scanning electron microscopy. In both cases, similar to other Macrobiotidae (Węglarska, 1982; Poprawa etal., 2015) egg capsule was composed of thin vitelline envelope and three-layered chorion. The chorion consisted of: (1) the inner, medium electron-dense layer – endochorion, (2) the middle, labyrinthine layer and (3) the outer, medium electron-dense layer – exochorion. The yellow chorion of Richtersius coronifer was covered with elongated processes having irregular granulation ontheir surface. These processes were empty inside. They were formed by evagination of exochorion. The basic chorion connecting processes was smooth and covered with irregular granulation. The chorion of Macrobiotus pallari was white. Its surface was covered with conical processes and areolation between them. The tips of processes were elongated and formed bushy structure. The surface of conical processes has a form of sculpture composed of thin rings. The processes that were empty inside, were formed by evagination of exochorion and labyrinthine layer.