Chitinozoan biofacies of late early Llandovery (Coronograptus cyphus) age in the East Baltic

Four lateral chitinozoan biofacies, mainly defined by the distribution of Cyathochitina species, are recognized from the uppermost lower Llandovery strata (Coronograptus cyphus age) in 18 eastern Baltic sections. Cyathochitina kuckersiana (Eisenack, 1934) seems to have preferred shallow-water near-shore conditions and C. calix (Eisenack, 1931) deeper parts of the shelf, whereas C. campanulaeformis (Eisenack, 1931) is more widespread. Representatives of the genus Cyathochitina appear to be absent in most of the near-shore environment. However, these chitinozoan biofacies are probably of only regional significance and occur where calcareous muds (which formed calcitulites) were deposited.