Genus Helioferrusa nov. gen.

Type species. Helioferrusa hollandei nov. gen., nov. sp.

Diagnosis. Skeleton of Heliodiscus type but bearing a peripheral porous ring instead of spines. Microsphere eccentric in the outer medullary shell.

Etymology. The generic name comes from the Greek helios – Sun and Odette Ferru who illustrated the radiolarian species from the monograph by Hollande & Enjumet (1960) with wonderful drawings similar in quality to those made by Adolf Giltsch for Haeckel’s 1887 monograph. Feminine gender.

Remarks. This genus resembles a Coccodiscus Haeckel from which it differs in having a double medullary shell with eccentric microsphere and originated very probably in Heliodiscus riedeli nov. sp. with which its cortical shell resembles very well and with which it co-occurs in the late middle Miocene assemblage from sample PROA 96P.

Range and occurrence. Late middle Miocene so far as known.