Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

Journal of Paleontology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by ZUYKOV, M. A. Articles by BUTTS, S. H. Search for Related Content GeoRef GeoRef Citation

GLYPTORTHIS (FOERSTE, 1914) AND BASSETTELLA NEW GENUS (BRACHIOPODA: ORTHIDA) FROM THE LATE ORDOVICIAN OF THE EAST BALTIC

¹ Department of Paleontology, St. Petersburg State University, 29, 16 Liniya, 199178 St. Petersburg, Russia, <zuykov@riand.spb.su>;
² Yale University, Peabody Museum, 170 Whitney Ave., P.O. Box 208118, New Haven, Connecticut 06520-8118, <susan.butts@yale.edu>

The first 20% of the full text of this article appears below.

	INTRODUCTION

 
THE GENUS Glyptorthis Foerste, 1914 is a rare component of the Late Ordovician to early Silurian brachiopod faunas of the East Baltic. Hints and Rõõmusoks (1997) reported on the occurrence of Glyptorthis in seven stratigraphic levels within the Upper Caradoc, Ashgill and Llandovery, in a paper summarizing the stratigraphy of Estonia. To date, however, very few of these brachiopods have been studied in detail. Three species from the Ashgill and Llandovery were established by Rubel (1962) and Rõõmusoks (1970), whereas some unnamed Caradoc taxa were listed only in the latter paper. Collections made since 1987 by S. S. Terentiev and M. A. Zuykov revealed that rare specimens of Glyptorthis-like brachiopods occur in fossiliferous lower Caradocian (Idavere Regional Stage) strata in the western part of the St. Petersburg region, northwestern Russia. These specimens, assigned herein to a new glyptorthid genus and species Bassettella gracilis, comprise the core of this paper. Moreover, generic affinities of Estonian species from the Ashgill currently assigned to Glyptorthis are discussed. The type specimen of J. Hall (1847) in the American Museum of Natural History (New York) and specimens from the type area in the Schuchert Brachiopod Collection in the Peabody Museum of Natural History, Yale University (New Haven), have been investigated for comparative purposes.

	MATERIAL AND LOCALITIES

 
The brachiopods described here were collected from localities in NW Russia, Estonia, and North America (Fig. 1). The Bassettella gracilis n. gen. and sp. fossil localities from the St. Petersburg region (NW Russia) are given in Figure 1, as is a correlation chart with the Estonian stratigraphic position of B. gracilis.

View larger version (32K):    FIGURE 1—Locality map and stratigraphic ranges of Glyptorthis Foerste, 1914 and Bassettella new genus in the Upper Ordovician rocks of North Estonia and northwestern Russia (St. Petersburg region). 1, Kõrgessaare . . . [Full Text of this Article]