Isolated asterozoan ossicles and pedicellariae occur in micropalaeontological samples from the Darriwilian (Middle Ordovician) of the Mishina Gora section, north-western Russia. The well-preserved Bursulella unicornis type fossils represent the oldest hitherto record of asterozoan pedicellariae. The accompanying ossicles are not diagnostic but allow their tentative placement within the asteroid stem group. The abundance of disarticulated ossicles in the samples proves that asterozoans were not as rare as they have been considered and were important members of Ordovician ecosystems in the Baltic Palaeobasin.

Key words: Echinodermata, Asteroidea, Bursulella, pedicellariae, Ordovician, Baltica.

Oive Tinn [oive.tinn@ut.ee] and Leho Ainsaar [leho.ainsaar@ut.ee], Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411, Tartu, Estonia.