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Ifecysta pachyderma
Ifecysta pachyderma Jan du Chêne and Adediran, 1985
Holotype: Jan du Chêne and Adediran, 1985, pl.15, figs.1-2, text-figs.6a-b
Locus typicus: Benin-Ore Highway, Km 41, Nigeria
Stratum typicum: Late Palaeocene-Early Eocene
Original description: Jan du Chêne and Adediran, 1985, p. 20
Cyst skolochorate with a ellipsoidal to fusiform body with distinct apical and antapical horn-like protrusions. The endophragm and periphragm are closely appressed together even in the apically and antapically. The fibrous periphragm forms large, solid penitabular processes. The paratabulation is indicated by the penitabular processes distribution and the precingular (3" only) archeopyle. Paratabulation formula is: pr, 4", 6", 7c, 6""", 1p, 1"""", 5s (see fig. 3a - 3i). The paracingulum is well defined by a row of cingular processes, with distinct rectangular bases. The parasulcus is marked primarily by the presence of small sulcal processes (which correspond to the sulcal paraplates as, ra, rs, 1ps, 1s, see text-fig. 6i) and the ventral offset of the paracingulum. Precingular and postcingular processes are well defined, rounded to subquadrangular in cross section and with slightly expanded distal ends. Small fibrous expansion, at the top of the apical horn-like protrusion, suggests the presence of (a) preapical structure(s). The operculum is generally free, but may be adherent on some specimens.
Dimensions: Range: Overall length (including apical and antapical horn like protrusions) 95-110 µm; Overall width 50- 62 µm; Processes length 18- 30 µm Number of specimens measured: 15.
Holotype: Jan du Chêne and Adediran, 1985, pl.15, figs.1-2, text-figs.6a-b
Locus typicus: Benin-Ore Highway, Km 41, Nigeria
Stratum typicum: Late Palaeocene-Early Eocene
Original description: Jan du Chêne and Adediran, 1985, p. 20
Cyst skolochorate with a ellipsoidal to fusiform body with distinct apical and antapical horn-like protrusions. The endophragm and periphragm are closely appressed together even in the apically and antapically. The fibrous periphragm forms large, solid penitabular processes. The paratabulation is indicated by the penitabular processes distribution and the precingular (3" only) archeopyle. Paratabulation formula is: pr, 4", 6", 7c, 6""", 1p, 1"""", 5s (see fig. 3a - 3i). The paracingulum is well defined by a row of cingular processes, with distinct rectangular bases. The parasulcus is marked primarily by the presence of small sulcal processes (which correspond to the sulcal paraplates as, ra, rs, 1ps, 1s, see text-fig. 6i) and the ventral offset of the paracingulum. Precingular and postcingular processes are well defined, rounded to subquadrangular in cross section and with slightly expanded distal ends. Small fibrous expansion, at the top of the apical horn-like protrusion, suggests the presence of (a) preapical structure(s). The operculum is generally free, but may be adherent on some specimens.
Dimensions: Range: Overall length (including apical and antapical horn like protrusions) 95-110 µm; Overall width 50- 62 µm; Processes length 18- 30 µm Number of specimens measured: 15.