Operculodinium ornamentum (Jain and Tandon, 1981) Jain and Garg, 1991

Originally Polysphaeridium, subsequently (and now) Operculodinium.

Holotype: Jain and Tandon, 1981, pl.2, fig.35
Age: Middle Eocene

Original description (Jain & Tandon, 1981):
Polysphaeridium ornamentum sp.nov. (pl. II-35)
1975 Cordosphaerdium sp. A, in Williams & Brideaux; pg. 15, fig. 8.
Holotype: Pl. II-35; BSIP Slide no. 6430 ; coordinates: 120.5x14.5.
Diagnosis: cyst ovoidal, periphragm thick, surface coarsely granulate to verrucate ; processes numerous, more than 60, long, imple or sometimes branched, spongy at point of origin, distally open, recurved. Archaeopyle not clearly marked, probably apical.
Measurements: Overall cyst size: 140-170 µm; central body size: 70-90 X 90-110 µm; length of processes up to 55 µm.
Comparison: Polysphaeridium ornamentum sp.nov. compares best with P. giganteum Caro (1973) in having large size but differs in its prominent periphragm ornamentation and recurved distal end of the processes.
Type locality: Jhadwa, S-W Kachchh, India.
Horizon: Middle Eocene.