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Cryptostome Bryozoan Stictoporella Simplex (POˇCTA, 1894) From

N. Jb. Geol. Paläont. Abh. 260/1, 79–85 Article published online January 2011 Cryptostome bryozoan Stictoporella simplex (POCTAˇ , 1894) from the Silurian of Bohemia Andrej Ernst, Kiel, Stˇ ˇepán Manda and Kamil Zágorˇsek, Prague With 3 figures and 1 table ERNST, A., MANDA, S. & ZÁGORSEKˇ , K. (2011): Cryptostome bryozoan Stictoporella simplex (POCTAˇ , 1894) from the Silurian of Bohemia. – N. Jb. Geol. Paläont. Abh., 260: 79–85; Stuttgart. Abstract: New material of the cr yptostome species Stictoporella simplex (POCTAˇ , 1894) from the Late Silurian of Bohemia w as studied using thin sections. Mor phology of this species was investigated in detail. Stictoporella simplex represents the y oungest known species of the genus Stictoporella, and its first record outside the Silurian tropical carbonate platforms which suggests the existence of connections betw een the Altay and Bohemia re gions apparently near the end of the Wenlock. Key words: Silurian, Bohemia, cryptostome Bryozoa, taxonomy. 1. Introduction distincta, and L. simplex. PRANTL (1935) revised the genus Lemattopora and realised that its diagnosis does Stenolaemate bryozoans belonging to the Order not correspond with the type material and contains Cryptostomata VINE, 1884 were an important group characters of different genera. He placed tw o species in Palaeozoic marine communities (G ORJUNOVA & (L. frondosa, L. simplex) in the ptilodictyine genus LAVRENTJEVA 1993; GORJUNOVA 1996). The Ptilodic- Stictoporella ULRICH, 1882. Lemattopora angulosa tyina are a suborder of Cryptostomata characterized was placed in the genus Coenites EICHWALD, 1829, by an erect bifoliate g rowth habit. These bryozoans which is actually a coral, whereas ?L. indistincta was appeared and diversified during the Middle and Late assigned to the cystoporate genus Fistulipora. Ordovician, and then g radually diminished from the BASSLER (1953: G138) apparentl y independently Silurian to the Permian (KARKLINS 1983). The last assigned Lemattopora as junior synon ym of Sticto - ptilodictyine species w as recorded from the Lo wer porella. The revision of PRANTL (1935) was not cited Permian of Ellesmere, Canada (E RNST & NAKREM by BASSLER (1953). KARKLINS (1983: 518) followed 2007). Except for a few studies in North America and both PRANTL (1935) and B ASSLER (1953) and as - Russia, little is known about the distribution of ptilo- signed Lemattopora as a junior synon ym of Sticto - dictyines in the Silurian and Devonian. porella. POCTAˇ (1894) erected the genus Lemmatopora PRANTL (1935) produced a precise description of from the Silurian deposits of Bohemia (Dlouhá Hora, his own material of Stictoporella frondosa [= simplex] probably Ludlow in age). He included four ne w (POCTAˇ , 1894), because the type material of P OCTAˇ species in this genus: L. angulosa, L. frondosa, ?L. in - (1894) is badly preserved. His description was accom- © 2011 Schweizerbart’sche Verlagsbuchhandlung, Stuttgart, Germany www.schweizerbart.de DOI: 10.1127/0077-7749/2011/0130 0077-7749/2011/0130 $ 1.75.

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