Family CRYPTOLARNACIIDAE Dumitrica, 1989 n. stat.

Cryptolarnaciinae Dumitrica, 1989: 241-242 . — De Wever et al. 2001: 156. — Afanasieva et al. 2005: S287. — Afanasieva & Amon 2006: 130.

TYPE GENUS. — Cryptolarnacium Dumitrica, 1989: 246 [type species by monotypy: Cryptolarnacium hexastylus Dumitrica, 1989: 246].

INCLUDED GENERA. — Coccolarnacium Dumitrica, 1989: 242 . — Cryptolarnacium Dumitrica, 1989: 246 . — Globolarnacium Dumitrica, 2020: 13. — Phacolarnacium Dumitrica, 2020: 7. — Pylolarnacium Dumitrica, 2020: 16.

NOMEN DUBIUM. — Staurosphaerantha .

DIAGNOSIS. — The shell of the phorticiid-type structure is completely hidden within a cortical shell, that strikingly resembles the cortical shell of some co-occurring spumellarians. However, in Cryptolarnaciidae this layout is separated by an empty space or a loose spongy framework.

STRATIGRAPHIC OCCURRENCE. — Late Paleocene-Late Eocene.

REMARKS

This group is raised herein from the subfamily Cryptolarnaciinae (originally included in family Larnacillidae) to the family level in order to maintain rank consistency. Internal skeletal structure for Coccolarnacium (Dumitrica 1989: pl. 10, figs 1-4; pl. 14, figs 2-4, 9) and Cryptolarnacium (Dumitrica 1989: pl. 10, figs 5, 6, 10; pl. 14, figs 5, 6) was illustrated. This family member is found in plankton samples from the Pacific Ocean, South China Sea and Eastern Indian Ocean (e.g., Onodera et al. 2011: pl. 4, fig. 13).