Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 20. 2002. (Budapest, 2002)

stmcture. The inner structure of Retiailopbragmium acutidorsatum was examined by QCHA & ZAPLETALOVA (1963). Strarigraphical range — It is known from all HANÏÏŒN localities (HANTKEN, 1875a, b), from the Middle Eocene formations to the Lower Oligocène Kiscell Clay Formation (Table 2). In Hungary it is rarer in the Buda Marl than in the Kiscell Clay. It ranges from the Middle Eocene to the Early Miocene (Eggenburgian). It is very frequent in the Lower Eocene and Upper Kiscellian, mainly in the upper part of the Kiscell Clay [horizon of agglutinated foraminifers (MAJZON 1966)]; associations with agglutinated foraminifers (HORVÁTH 1998); Anomalina affmis zone (SZTRÁKOS 1982). In Europe Reticulophraginium acutidorsatum occurs in the Paleogene. It is frequent in the Upper Eocene and Oligocène formations (N Italy, Monte Brione, Possagno, riAGN 1952; BRAGA & GRÜNIG in BRAGA et al 1975). In the foreland molasse sediments it ranges from Upper Eocene to Oligocène, but it is also known from the Eggenburgian and the Lower Ottnangian (HAGN 1956; LÜHR 1962; WENGER 1987; REISER 1987). In the Central Paratethys, it ranges from the Late Eocene to the Late Eggenburgian (ClCHA et al. 1998). In Croatia, it occurs in the Rupelian (SlKIC 1985). In the North Sea Reticulophragmium acutidorsatum occurs from the Middle Eocene to the Oligocène (GRADSTEIN & BERGGREN 1981). Ecology — It is a typical epifaunal, detnvore and euhalin form in the neritic zone, frequents in the fine sandy clay fades (MURRAY 1973,1991, MORKHOVEN et al. 1986, HORVÁTH 1998). Reticidophragmium rotundidorsatum (HANTKEN, 1875) (Plate I: 2; Plate II: 2) 1871 Haplophragmium rotundidorsatum n. sp. — HANTKEN, p. 128 (in list) 1875a Haplophragmium rotundidorsatum n. sp. — HANTKEN, S. 12, Taf. I, Fig. 2. 1875b Haplophragmium rotundi-dorsatum — HANTKEN, p. 10, pl. I, fig. 2. non 1960 Haplophragmoides rotundidorsatus (HANTKEN) — SUBBOTINA, pl. II, figs 3a-c. 1962b Haplophragmoides latidorsatus (BORNEMANN) — MAJZON, pi. XXIX(I), fig. 2. 1963 Cyclammina rotundidorsata (HANTKEN) — ClCHA & ZAPLETALOVA, p. 103, Abb. 14. non 1969 Haplophragmopides rotundidorsatum (HANTKEN) — KRAEVA & ZERNECKIJ, p. 20, pi. 5, figs lOa-b. 1970 Cyclammina rotundidorsata (HANTKEN) — KIESEL, S. 188, Taf. Ill, Fig. 1. 1971 Cyclammina rotundidorsata (HANTKEN) — POPESCU &: IVA, pl. I, fig. 6. 1973 Haplophragmoides latidorsatus (BORNEMANN) — NAGYNÉ GELLAI, p. 440. 1975 Haplophragmoides rotundidorsatum (HANTKEN) — BRAGA & GRÜNIG in BRAGA et al, p. 102. 1978 Cyclammina rotundidorsata (HANTKEN) — SZTRÁKOS, p. 64, pi. 2, figs 6a-b. 1979 Cyclammina rotundidorsata (HANTKEN) — SZTRÁKOS, p. 58, pi. 2, figs 6a-b. 1981 Cyclammina rotundidorsata (HANTKEN) — GRADSTEIN & BERGGREN, p. 256, pl. VII, figs 9-12. 1981 Cyclammina rotundidorsata (HANTKEN) — MORGIEL & OLSZEWSKA, p. 14, pi. 4, fig. 15. 1982 Cyclammina rotundidorsata (HANTKEN) — SZTRÁKOS, pl. 1, figs 15a-b. 1987 Cyclammina rotundidorsata (HANTKEN) — WENGER, S. 244, Taf. 1, Fig. 11, 16; Abb. 23/2. 1994 Reticulophragmium rotundidorsata (HANTKEN) — SCHRÖDER-ADAMS & MCNEIL, p. 41, pl.8, fig.5a-c. 1998 Reticulophragmium rotundidorsatum (HANTKEN) — ClCHA et al., p. 124, pl. 5, fig. 5. part 1999 Reticulophragmium rotundidorsatum (HANTKEN) — DARAKCHIEVA, p. 8. Lectotype —M.99.40. Type locality — Budapest, Újlak. Type level — Upper part of the Kiscell Clay Formation, late Kiscellian, P 21a zone. Material — 15 specimens remained in the Hantken Collections in Hungary (Table 2). Dimensions — Diameter ranges 2-3 mm, thickness 0.6-1.2 mm. Diagnosis — The broad and low chambers planispirally coiled, involute. The number of chambers 7-10 per whorl. The sutures nearly radial, the periphery rounded The umbilicus is deep. The wall agglutinated with very thin imperforate outer layer. The aperture a low slit at the base of the apertural surface. Remarks — ITANTKEN had already mentioned the special new form of the Kiscell Clay in 1871, but the description was given only in 1875. It differs from H. latidorsatus (BORNEMANN 1855) in the inner structure, in the number of the chambers, the size, and the shape of the dorsal periphery. Without comments, NAGYNÉ GELLAI (1973) regarded H. rotundidorsatus as the synonym of H. latidorsatus (BORNEMANN, 1855). Fragmenta Palaeontologica Hungarica 20, 2002 Stratigraphical range —The occurrence of Reticulophragmium rotundidorsatum is sparser than that of Reticuloploragmium acutidorsatum (Table 3) from lower and upper part of the Clavulina Szabói layers (riANTKEN, 1875a, b). In Hungary it is known from Upper Eocene-Oligocene sediments, but this species is not frequent. Some specimens occur also in the upper part of the Kiscell Clay Formations (SZTRÁKOS, 1979,1982; HORVÁTH 1980,1998). In West Europe it occurs from Upper Eocene to Lower Miocene (KlESEL 1970; WENGER 1987). In the Central Paratethys it ranges from the Upper Eocene to the Lower Miocene (Eggenburgian), it is typical in the Oligocène (ClCHA et al. 1998). In the External Carpathians Reticulophragmium rotundidorsatum occurs in the Oligocène (MORGIEL & OLSZEWSKA 1981). In South Bui garia it ranges from the Middle to the Late Eocene (DARAKCHIEVA 1999). In the North Sea sediments it occurs from Middle Eocene to the Oligocène (GRADSTEIN & BERGGREN, 1981). Ecology — It is a typical epifaunal, detritivore, euhalin and cold water dweller form, being frequent in the upper bathyal sandy clay and sand facies (MURRAY 1973,1991).