Simple Summary Phylum Retaria and Phylum Cercozoa consists of the siliceous planktonic organisms, commonly referred to as Radiolarians, were investigated from 200 m depth to the surface in the eastern Indian Ocean (80.00°–96.10° E, 10.08° N–6.00° S) during

Siliceous planktonic species of the phyla Retaria and Cercozoa were investigated from the surface to a 200 m depth around the eastern Indian Ocean (80.00°–96.10° E, 10.08° N–6.00° S) during a 2-month cruise (10 April–13 May 2014). These species are commonly

The vertical distribution of radiolarians was investigated by using a closing-type net with 63 μm mesh in the Okhotsk Sea (Station NU'2, near Bussol' Strait) down to 1000 m depth and in the northwestern North Pacific (Oyashio region, Station X) down to