Distribution of lingulate brachiopods in the Early Ordovician of the East Baltic

In the East Baltic, the late Tremadoc and early Arenig interval- is associated with a major change in the composition of the benthic faunas; during this time, the low diverbity assemblages were replaced by medium to high diversity bentic assemblages including brachiopods, bryozoans, trilobites, ostracodes, and echinoderms. The brachiopods constitute the most important components of this new fauna. The most comprehensive study of the lingulate brachiopods from these beds was published by Gorjanov (1969), but the detailed distribution of lingulates in the early Ordovician of the East Baltic is still poorly known. This brief review of the distribution of lingulate brachiopods in the Hunneberg, Billingen and Volkhov stages is based mainly on field work in Estonia and Ingria, during 1989-1993, the main results of which are still unpublished.