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N. Jb. Geol. Paläont. Abh. 2007, vol. 243/3, p. 299 – 303, Stuttgart, March 2007, published online 2007
A new Miocene Bryozoa from the Sarmatian of the Danube basin Kamil Zágor sek, ˇ Prague With 7 figures
ZÁGORSˇ EK, K. (2007): A new Miocene Bryozoa from the Sarmatian of the Danube basin. – N. Jb. Geol. Paläont. Abh., 243: 299–303; Stuttgart. Abstract: New species of Sarmatian Bryozoa Celleporina dubovaensis sp. n. has been found in the section Dubová (Slovakia) and described in details. The new species differs from all other known species of Celleporina having combination of thick radial ribs in the perforated area of the ovicells, only one suboral avicularium per zooecium and rare, very large vicarious avicularia. Key Words: Bryozoa, taxonomy, new species, Sarmatian.
1. Introduction The first Early Serravallian (lower Sarmatian) bryozoans from Slovakia were found at the locality Dubová (FORDINÁL et. al. 2006) and described by ZÁGORSˇ EK & FORDINÁL (2006). In summer 2006, additional specimens of colonies described as Celleporina sp. were collected. Detailed study of these new colonies shows that they belong to a new species which is described here as Celleporina dubovaensis sp. nov.
2. The Dubová section A very instructive and fossiliferous section near to the village of Dubová was excavated during construction works for a dump place below the eastern slopes of the Malé Karpaty Mts, about 10 km north of the town of Pezinok – western Slovakia (Fig. 1). Here, grey to greenish clays of the Vráble Formation contain thin tempestite intercalations of molluscan shell debris (FORDINÁL et. al. 2006). An abundant fauna of
DOI: 10.1127/0077-7749/2007/0243-0299
molluscs (gastropods, bivalves), foraminifers, ostracods, bryozoans and calcareous cysts of the algae ´ has been found in Chalmasia morelleti POKORNY these shell beds. A detailed description of the section is given by FORDINÁL et.al. (2006). The occurrence of the mollusks Ervilia dissita dissita EICHWALD and ostracods Cytheridea hungarica (ZALÁNYI) and Aurila mehesi (ZALÁNYI) shows the deposit to belong to the Early Sarmatian biozone of Cytheridea hungarica – Aurila mehesi (FORDINÁL et al. 2006).
3. Material and methods Samples for detailed study were taken from thin sandy layers intercalated within the clay, with macroscopically visible fragments of molluscs. The samples were washed, sieved using a 0,025 mm diameter mesh and dried. Ultrasonic cleaning was undertaken before study the bryozoans using a Jeol type JSM-6400 SEM in the Paleontological department of Vienna University. Measurements was made by SemAfore® 3.0 pro Jeol software. Specimens described are deposited in the National Museum, Prague.
0077-7749/07/0243-0299 $ 1.25 © 2007 E. Schweizerbart’sche Verlagsbuchhandlung, D-70176 Stuttgart
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Fig. 1. Geographical sketch of the locality Dubová.
4. Systematic palaeontology Phylum Bryozoa EHRENBERG, 1831 Order Cheilostomatida BUSK, 1852 Suborder Ascoporina LEVINSEN, 1909 Infraorder Lepraliomorpha GORDON, 1989 Superfamily Celleporoidea JOHNSTON, 1838 Family Celleporidae JOHNSTON, 1838 Genus Celleporina GRAY, 1848 Celleporina dubovaensis sp. nov. Figs. 2-6 2006
Celleporina sp. – ZÁGOR Sˇ EK & FORDINÁL, p. 96, fig. 2.6.
Holotype: Specimen depicted in Figs. 2 and 4-6, from the Dubová locality, deposited in the National Museum, Prague under the number P2-P 01235. Paratypes: 7 specimens from the Dubová locality, deposited in the National Museum, Prague under the numbers P2-P 01236 – P2-P 01242 and P2-P 01293 – P2-P 01295. Etymology: After the name of the locality Dubová. Type locality: Dubová village, Slovakia. Type horizon: Miocene – lower Serravallian (Sarmatian). Diagnosis: Colony encrusting, multilamellar. Zooecia arranged chaotically, with marginal areolae only and terminal orifice with very wide sinus. Suboral avicularia on a short peduncle. Vicarious avicularia large, rare. Ovicell
hyperstomial with a perforated area (tabula) of entooecium. Dimensions: maximum colony size: 1258 × 1400 µm; minimum colony size: 876 × 968 µm average colony size: 1065 × 1180 µm height of the colony hight: 423 µm width of the zooecia: 183 – 279 µm, average = 229 µm width of the orifice: 61 – 94 µm, average = 73 µm average dimension of adventitious avicularia: 53,1 × 66,5 µm average dimension of vicarious avicularia: 189,0 × 253,1 µm average dimension of ovicell window: 112,3 × 114,7 µm Description: The colony is encrusting, multilamellar, in some colonies preserving a subcircular hole that may indicate an original algal or other soft substratum. Zooecia are recumbent at colony margins, suberect, arranged chaotically on the surface of the colony, but a predominant direction of the orifice is sometimes observable (Fig. 2). Zooecia are oval to circular with convex, nonporous frontal walls except for rare marginal areolar pores varying in number from 4 to 9 (Fig. 3). Lateral walls are thick and usually salient (Fig. 3). The orifice is situated on a short peristome and has a well-developed, wide sinus usually more than half of the maximum orifice width. Condyles are slight, sometimes scarcely visible. Avicularia of two types: adventitious and vicarious. Aventitious avicularia are suboral, circular, situated on long peduncles (Fig. 5), usually one near to the proximal margin of each orifice, rarely paired. Vicarious avicularia are rare, as wide as autozooecia and usually also bear small suboral avicularia, with a very wide, smooth and slightly convex rostrum (Fig. 4). A pivotal bar is developed in both types of avicularia. Ovicells are hyperstomial, globular, mostly slightly immersed, some-
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Figs. 2-3. Celleporina dubovensis sp. nov. 2 – General view of the holotype P2-P01235 showing chaotic growth of the frontally-budded autozooecia with same alignment of orifices, arrangement of ovicells and small suboral avicularia. Scale bar 1 mm. 3 – Celleporina dubovensis sp. nov. General view of paratype P2-P 01241 showing areolar pores, small suboral avicularia and wide orifical sinuses. Scale bar 100 µm.
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Figs. 4-6. Celleporina dubovensis sp. nov. 4 – Detail of a vicarious avicularium showing wide rostrum, pivotal bar and one suboral small avicularium. 5 – Celleporina dubovensis sp. nov. Lateral view of autozooecia showing sub-oral avicularia on top of long peduncules. 6 – Celleporina dubovensis sp. nov. Detail of ovicell showing semicircular uncalcified window covered by radial ribs which are wider on the margin and thinner in the centre of the window. – Scale bars 100 µm.
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times prominent, with a perforated, uncalcified frontal area and calcified smooth, nonporous margins. The perforated area is subcircular to semilunar and covered by 5 to 7 thick radial ribs. The thickness of the ribs varies, the marginal ribs being almost twice the thickness of the central ribs (Fig. 6). Ovicellate zooecia may develop two suboral avicularia. Remarks: Due to the presence of a sinuate orifice, smooth frontal wall with scattered marginal areolar pores, hyperstomial ovicell with perforated frontal area and the absence of oral spines, this species is assigned to Celleporina as understand by HAYWARD & RYLAND (1999). Celleporina pygmaea (NORMAN, 1868) as redescribed by HAYWARD & RYLAND (1999) is the most similar species to Celleporina dubovaensis sp.nov. It differs mainly in having very long peristomes, an orbicular orifice and in lacking vicarious avicularia. Very similar also is Celleporina robertsoniae (CANU & BASSLER, 1923) as redescribed by SOULE et al.(1995) in which, however, vicarious avicularia are very common and the perforated area of the ovicell is covered by many narrow ribs. Celleporina miniscula POUYET, 1973 is also similar to Celleporina dubovaensis sp.nov. in having only one suboral avicularium and a wide sinus. The perforated area of the ovicells of Celleporina miniscula POUYET, 1973 is, however, covered by fused ribs and only a few marginal pores are observable. Schismopora rostrata MALECKI, 1958 also resemble the described species, but differs in having a much larger orifice (width 90-120 µm), smaller adventitious avicularia and many more ribs (15-18) on the ovicells. Furthermore, the umbo of the suboral avicularia is much larger in Schismopora rostrata than in Celleporina dubovaensis sp. nov. No known species of Celleporina has the combination of thick radial ribs in the perforated area of the ovicells, only one suboral avicularium and rare, very large vicarious avicularia.
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Vienna University, Austria) for their help with photography and comments. My thanks go also to Dr. P. D. TAYLOR from NHM London, who enhanced the language of this paper and helped me with useful comments. ˇ through Project The research was supported by GACR 205/06/0637 and by Ministry of Culture of Czech Republic MK 00002327201.
References FORDINÁL, K., ZÁGOR Sˇ EK, K. & ZLÍ NSKÁ, A. (2006): Early Sarmatian biota in the northern part of the Danube Basin (Slovakia). – Geologica Carpathica, 57 (2): 123-130. HAYWARD, P. J. & RYLAND, J. S. (1999): Cheilostomatous Bryozoa Part 2: Hippothooidea-Celleporoidea. Synopses of the British Fauna (New Series) 14 (second Edition). – 416 pp. MALECKI, J. (1958): Mszywioly Tortonskie z Gliwic Starych. – Rocznik Polskiego Towarzystwa Geologicznego, 28 (2): 169-194. POUYET, S. (1973): Revision Systematique des Cellepores (Bryozoa, Cheilostomata) et des Especes Fossiles Europeennes. Analyse de Quelques Populations a Cellopores dans le Neogene du Bassin Rhodanien. – Doc. Lab. Geol. Fac. Sci. Lyon, 55: 1-266. SOULE, D. F., SOULE, J. D. & CHANEY, H. W. (1995): The Bryozoa. – In: BLAKE, J. A., CHANEY, H. W., SCOTT, P. H. & LISSNER, A. L. (Eds.): Taxonomic Atlas of the Santa Maria Basin and Western Santa Barbara Channel 13, 1-344; Santa Barbara (Santa Barbara Museum of Natural History). ZÁGOR Sˇ EK, K. & FORDINÁL, F. (2006): Lower Sarmatian Bryozoa from brackish sediment in the northern part of the Danube Basin (Dubová, Slovakia) – Linzer biologische Beiträge, 38 (1): 93-99. Manuscript received: September 20th, 2006. Revised version accepted: December 4th, 2006.
Acknowledgements
Address of the author:
I am very thankful to Dr. FORDINÁL from Slovak Geological Survey, who enabled me to study first Sarmatian Bryozoa from Slovakia. Many thanks are given also to Prof. N. VÁVRA and Dr. R. ZETTER (Institute of Palaeontology,
KAMIL ZÁGOR Sˇ EK, Department of Palaeontology, National Museum, Václavske nam. 68, CZ – 115 74 Prague, Czech Republic; E-mail:
[email protected]
