ABSTRACT: Two new species, Calcidiscus salamis sp. nov. and C. odebodea sp. nov. are described from themarine offshore Niger Delta Neogene sequence. Calcidiscus salamis is structurally similar to C. fuscus but has a closed central area. Calcidiscus odebodea differs from C. leptoporous in having strongly curved sutures. The new forms consistently occur throughout the LateMiocene to Early Pliocene offshore eastern and western Niger Delta sequences. They have the same stratigraphic range: NN11-NN13 zones (Messinian to Zanclean). The combination of their widespread geographic occurrence and short stratigraphic rangemakes them excellent index species for the high-resolution biostratigraphy of theNiger Delta marine offshore sequences where most Calcidiscus forms have much longer ranges. KEYWORDS: Calcareous nannofossil, Biostratigraphy, Calcidiscus, Niger Delta.