Macrostylocrinus bornholmensis Laursen, 1940, a forgotten Silurian crinoid from Denmark

The monobathrid camerate crinoid Macrostylocrinus bornholmensis Laursen has an unfortunate history. It was published in a journal not commonly consulted by echinoderm workers and, worse, in time of war; written in a language not in common use for crinoid studies; and described by a stratigrapher, not an expert on pelmatozoans. These and other factors combined to ensure that M. bornholmensis has not been reassessed since it was first described almost 80 years ago, despite belonging to a genus well-known from the Lower Palaeozoic. Macrostylocrinus bornholmensis is Llandovery (Telychian) and not Wenlock as has been reported elsewhere. Diagnostic features include a column that does not bear radices close beneath the cup; a heteromorphic mesistele with five orders of regularly inserted internodals; three basal plates; smooth thecal plates with central folds following rays; and ten pinnulate free arms that are biserial distally. Macrostylocrinus bornholmensis is distinctly different in morphology from well-known, congeneric species described from the Lower Palaeozoic of northern Europe.