Notes on selected Cretaceous echinoids from south-central Sakhalin, Far East Russia

AbstractFrom Albian, Santonian and Campanian strata in south-central Sakhalin, four echinoid taxa are described, illustrated and discussed. In Far East Russia, echinoids are rare constituents amongst mid- and Late Cretaceous macrofaunal assemblages in which inoceramid and non-inoceramid bivalves, plus heteromorph and non-heteromorph ammonites predominate. The sole regular species in the present lot is represented by an incomplete external mould of a primary spine of a rhabdocidarid,Polycidaris(?) sp., from the lower Campanian. Irregular taxa include a fragmentary, specifically indeterminate ‘pygurid’,Echinopygus(?) sp., of late Albian age, as well as two spatangoids. One of these, a toxaste…