Similar to Hexacontium armatum/hostile, except that pores on outermost shell are larger and more irregular in size and distribution. May have one medullary shell (?). It is probable that Hexacontium aristarchi is a developmental form of Cromyomma circumtextum, from which it differs by lacking the outermost, very slender and delicate fourth shell. Outermost shell diameter without spines: ca. 130 µm.
Ref.: Boltovskoy and Riedel (1980).