The term “melanosclerite” was first introduced by Eisenack (1942) to describe problematic rod-shaped organic microfossils recovered from Ordovician and Silurian glacial erratics from the Baltic region. To date, melanosclerites have been recorded from marine sediments and erratic boulders from the Lower Cambrian (Winchester-Seeto and McIlroy 2006) to the Late Devonian (Cashman 1992), although published records and detailed descriptions of melanosclerite taxa remain scarce in relation to other microfossil groups. (From: Trampisch & Butcher 2010, https://doi.org/10.1007/s12542-009-0042-4).