Reprint of 'Radiolaria from the lower Cenomanian (Upper Cretaceous) of Crimea. Part 1. Spumellaria'

摘要

Well-preserved Late Cretaceous (early Cenomanian) radiolarians were recovered from two sections in Crimea: Bodrak River and Sel'-Bukhra Mountain sections. Abundant and diverse representatives of order Spumellaria were recognized and studied. Four new radiolarian species: Becus naidini nov. sp., B. tauricus nov. sp., Praeconocaryomma? bodrakensis nov. sp., and Savaryella? nikishini nov. sp. were described. Moreover, stratigraphical ranges of species Archaeospongoprunum sphaericum Bragina, Crucella lata (Lipman), Patellula cognata O'Dogherty, P. verteroensis (Pessagno), Spongodiscus quasipersenex Bragina were exactly defined (their lower limits are expanded to the lower Cenomanian). The upper limit of stratigraphic range of "Cenodiscus" alievi Pessagno is expanded to the lower Cenomanian. Our results suggest that two rare taxa "Cenodiscus" alievi Pessagno (California Coast Ranges) and Spongodiscus quasipersenex Bragina (West Sakhalin Mountains) are reported for the first time in the Tethyan regions.