Late Turonian and Early Coniacian ventriculitid sponges (Lychniscosida) from Opole Trough (southern Poland) and their palaeoecological significance

Eight species of ventriculitid sponges (Order Lychniscosida Schrammen, 1903) are described from the Upper Turonian marly limestones and Lower Coniacian marls of the Opole Trough (southern Poland). Among them four have not previously been noted in this area. Two species, Astropegma stellata (Roemer, 1840) and Leiostracosia robusta (Schrammen, 1902) are reported from Turonian strata for the first time. The occurrence of ventriculitid sponges in the Upper Turonian–Lower Coniacian succession of the Opole Trough indicates a soft- bottom, calm-water environment, with depths below the storm-wave base and a low rate of sedimentation.