orcadia (protist) orcadia (protist) orcadia is a monotypic genus of planktonic foraminifera belonging to the order globigerinida. the phylogenetic position of this genus remains enigmatic; it was originally assigned to the family hastigerinidae, but was later moved to globigerinellidae. orcadiatemporal range: pleistocene–present, scientific classification domain: eukaryota clade: diaphoretickes clade: sar phylum: retaria infraphylum: foraminifera class: globothalamea order: globigerinida family: globigerinellidae genus: orcadiaboltovskoy & watanabe 1982 type species hastigerinella riedelirögl & bolli 1973 description orcadia includes species characterized by a low trochospiral and thin test; an interiomarginal, extraumbilical to umbilical aperture with a rounded lip; and triangular spines located in the distal areas of the test chambers.