Ordovician lithistid sponges and gastropods from the Snåsa limestone, Nord-Trøndelag, Norway

Abstract

Fossil occurring in the Snåsa Limestone, observed in new road-cuts along the main E6 road near Snåsavatnet, Nord-Trøndelag, are illustrated and briefly described. Although the effects of Scandian deformation and crystallisation have made identification difficult, it seems clear that the fauna consists mainly of macluritid gastropods and related forms, and lithistid sponges of the genera Archaeoscyphia, Rhopalocoelia, possibly Hudsonospongia and either Anthaspidella or Zittelella. There is also a possibility that stromatoporoids and less likely, a rugose coral may be represented. The fauna is of mainly North American aspect and is considered to be of Middle, or possibly, Late Ordovician age.