Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 87. (Budapest 1995)

Dulai, A.: Middle Miocene (Badenian) lunulitiform Bryozoa from Szob (Börzsöny Mts., Hungary)

ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 87. Budapest, 1995 p. 35-54 Middle Miocene (Badenian) lunulitiform Bryozoa from Szob (Börzsöny Mts., Hungary) by A. DULAI, Budapest DULAI, A. (1995): Middle Miocene (Badenian) lunulitiform Bryozoa from Szob (Börzsöny Mts., Hungary). - Annls hist.-nat. Mus. natu. hung. 87: 35-54 Abstract - Szob is very famous for its mollusc fauna, however, several other fossil groups can be found in the yellowish-grey sand, which are hardly known. The free-living, so-called lunulitiform Bryozoa are represented by two species at Szob: Cupuladria vindobonensis BALUK et RADWANSKI and Reussirella haidingeri (REUSS). Up to now, lunulitiform Bryozoa have only been mentioned in fauna-lists at numerous localities in Hungary. The way of life and the ecological characters of lunulitiform Bryozoa are well known from studies on the recent representatives of free-living Bryozoa. Thus this group is suitable for the reconstruction of the paleoenvironment of Szob. Lunulitiform Bryozoa choose small-particle sand bottom below the wave base and they live in normal or slightly reduced salt water in tropical or subtropical climate. Lunulitiform species adapted themselves to life on soft sediments, where they may be the dominant elements among Bryozoa. With 28 figures and 7 tables. INTRODUCTION The research of Bryozoa is a very neglected area of Hungarian paleontology. This fact holds especially true for the Miocene Bryozoa of Hungary, although important data have been lost because of the lack of such studies, as Bryozoa are excellent environment indicators. The aim of this paper is to show the free-living, so-called lunulitiform Bryozoa of the famous Szob locality. Bryozoa are generally fixed marine animals. The special feature of the examined group is its free-living habitude. "Lunulitiform" is an old-established term derived from the name of Lunulites. However, sometimes it had different meanings in the works of different authors. This paper follows BALUK & RADWANSKI'S (1984a) classification in which three families belong to lunulitiform Bryozoa (Cupuladriidae, Discoporellidae, Lunulitidae). Lunulitiform Bryozoa appeared in the Late Cretaceous and live up to now. The way of life and the ecological characters of lunulitiform Bryozoa are well known from studies on their recent representatives. The type species of genus Cupuladria, C. canadensis (BUSK), is one of the most minutely examined Bryozoa species. Lunulitiform Bryozoa were studied extensively in the last few decades by European specialists. The family Cupuladriidae was defined by LAGAAU (1952). The vertical distribution of lunulitiform Bryozoa in the Tertiary of the Netherlands was examined by LAGAAU (1953). A very accurate biological and ecological study was made by LAGAAU (1963) on recent Cupuladria canadensis (BUSK). ANNOSCIA (1963) mentioned three lunulitiform species from the Miocene deposits of Italy. The external morphological characters of Cupuladriidae have been discussed in detail by COOK (1965a, b). Lunulitiform Bryozoa species were divided into four groups by COOK (Cupuladria canadensis group, Cupuladria guineensis group, Cupuladria owenii group, Discoporella umbellata group). HAKANSSON (1973) examined the internal morphology of Cupuladria biporosa CANU et BASSLER by orientated thin sections and a very