This work is dedicated to our late colleague Dr. Sandor Kovacs, who unfortunately died before the work was finished. He collected the majority of the sponge samples described in this paper and the main result of the stratigraphy of the reef carbonates is his contribution.

The hypercalcified sponge fauna of the Middle Triassic (Anisian–Ladinian) reef limestone exposed between Aggtelek-Jósvaf?-Egerszög (northern Hungary) is described. Almost all the identified species are chambered sponges (“sphinctozoa”). Only two fragments of a not determinable species of non-chambered species (“inozoa”) were identified. Hexactinellid sponges are not found. The majority of the Middle Anisian “sphinctozoans” are absolutely different genera, not known from the Permian reefs. The sponge fauna of the Triassic pioneer reefs in the Aggtelek Karst are distinctly small-scaled occurring in “Tubiphytes”-dominated carbonates. The following taxa are described: Amblysiphonella sp., Celyphia zoldana Ott, Pisa & Farabegoli, Colospongia catenulata catenulata Ott, C. catenulata macrocatenulata Scholz, Follicatena cautica Ott, Kovacsia baloghi (Kovacs), Solenolmia manon manon (Münster), S. radiata Senowbari-Daryan & Riedel, Olangocoelia otti Bechstadt & Brandner, Thaumastocoelia dolomitica Senowbari-Daryan, Zühlke, Bechstadt & Flügel, Thaumastocoelia cf., Th. cassiana Steinmann.