The fossilized remains of an isolated but once-thriving assemblage of the brittle starfish Furcaster cf. F. leptosoma (?) (Salter, 1857) record a singular event in the succession of late Devonian (Famennian?) marine life. In similar cases of fossil starfish mortality reported elsewhere, the cause of death was cited as suffocation due to rapid burial. In order to construct a paradigm which reflects the circumstances before and after the destruction of the assemblage in question, trace elements in the rock matrix were analyzed and correlated with neontologic data relative to important elements of the community and its environment. The circumstantial evidence points to burial as the ultimate factor in the death of the starfish. They were probably doomed by a series of subtle changes, of which they were not aware, taking place at the front of the delta they inhabited. The changes, hydrologic in nature, were instrumental in dulling the instincts of the starfish and preventing their escape from burial.

Abstract The palaeobiogeographical distribution of the six major clades of Ordovician echinoderms (asterozoans, blastozoans, crinoids, echinozoans, edrioasteroids and stylophorans) is analysed based on a comprehensive and up-to-date database compiling 3701 occurrences (1938 species recorded from 331 localities) of both complete specimens and isolated ossicles. Although historically biased towards a limited number of regions (Europe, North America, Russia), the resulting dataset makes it possible to identify six main palaeobiogeographical provinces for Ordovician echinoderms: Laurentia, Baltica, West Gondwana, East Gondwana, Avalonia and Siberia. At a global scale, the high endemicity of echinoderms during the Early to Middle Ordovician coincides with the time of maximum dispersal of continental masses. Late Ordovician faunas tend to become more cosmopolitan, possibly as a consequence of changing palaeogeography and/or relatively higher sea-levels in the Sandbian–Katian interval. Regional biodiversity patterns of Ordovician echinoderms confirm that their major diversification during the Ordovician is not a single, universal evolutionary event, but rather results from the complex addition of contrasted local evolutionary trends.