The mystery Radiolaria of the month is a Phaeodaria, which can not be unequivocally assigned to Euphysetta or Challengeron. Its shell is egg shaped with regular pores of equal pore size. It has a pronounced aboral spine, which is not articulated and two oral spines of equal length, which are articulated. The aboral spine is about the length of the shell or even longer. Beside these spines there are two minor spines, one at each side of the shell. The scale bar indicates 50 µm.
The species was found in the plankton from the Sea of Okhotsk. It
occurred most commonly in a station above the Kuril Basin at 48°41.9'N and 151°29.0'E between 50 and 130 m depth.