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Cristadinium cristatoserratum
Cristadinium cristatoserratum Head et al., 1989
Holotype: Head et al., 1989, pl.1, figs.10-11
Locus typicus: ODP leg 105, site 646, Labradoe Sea
Stratum typicum: Late Miocene
Original diagnosis: Head et al., 1989, p.456
Cysts dorsoventrally compressed, proximate, autophragmal with peridinoid outline and having an apical and two antapical horns. Cysts are pale to dark brown in color. Epicyst and hypocyst of approximately equal length. Antapical horns of equal length with solid acuminate tips. Wall thin, smooth to faintly granulate. Scattered small solid spines that may show linear arrangement are present on the hypocyst. The paracingulum is planar to weakly helicoidal and is continuous on the dorsal surface but separated ventrally by a wide unornamented sulcal region. Paracingular margins bear serrated or denticulate crests Epicyst devoid of scattered spines although bearing two pairs of serrated or denticulate crests (one ventral and one lateral pair) that occur along most of the length of the epicyst and converge toward the apex The archeopyle was not seen, the operculum apparently being in place in most specimens observed.
Dimensions. Holotype: length, 44 Ám. Range in cyst length, 33(42.3)54 Ám. Twelve specimens were measured.
Original description: Head et al., 1989, p.456
Sparsely scattered small solid spines (up to about 1.5 Ám long) occur on the hypocyst, particularly on the antapical horns Spines may have acuminate or truncated tips and commonly occur in short linear to arcuate groups, incompletely reflecting hypocyst tabulation. The paracingular margins have crests about 2 Ám high. The epicyst is devoid of scattered spines. Two pairs of parasutural crests (one pair on each side of the wide parasulcal region and one pair on the lateral margins) occur along most of the length of the epicyst and converge toward the apex. These crests are up to about 3 Ám high and are distally serrated or denticulate. Additional short crests were sometimes observed at the apex. Seventeen of the 18 specimens found were dorsoventrally compressed.
Affinities:
Head et al., 1989, p.456: Gerlachidium aechmophorum (Benedek, 1972) Benedek and Sarjeant, 1981 emend. Benedek and Sarjeant, 1981, described from the Oligocene of Germany, differs in having parasutural crests that are discontinuous both on the paracingular margins and on the epicyst, and that are higher (8-12 Ám) and less evenly serrated than for C. cristatoserratum.
Holotype: Head et al., 1989, pl.1, figs.10-11
Locus typicus: ODP leg 105, site 646, Labradoe Sea
Stratum typicum: Late Miocene
Original diagnosis: Head et al., 1989, p.456
Cysts dorsoventrally compressed, proximate, autophragmal with peridinoid outline and having an apical and two antapical horns. Cysts are pale to dark brown in color. Epicyst and hypocyst of approximately equal length. Antapical horns of equal length with solid acuminate tips. Wall thin, smooth to faintly granulate. Scattered small solid spines that may show linear arrangement are present on the hypocyst. The paracingulum is planar to weakly helicoidal and is continuous on the dorsal surface but separated ventrally by a wide unornamented sulcal region. Paracingular margins bear serrated or denticulate crests Epicyst devoid of scattered spines although bearing two pairs of serrated or denticulate crests (one ventral and one lateral pair) that occur along most of the length of the epicyst and converge toward the apex The archeopyle was not seen, the operculum apparently being in place in most specimens observed.
Dimensions. Holotype: length, 44 Ám. Range in cyst length, 33(42.3)54 Ám. Twelve specimens were measured.
Original description: Head et al., 1989, p.456
Sparsely scattered small solid spines (up to about 1.5 Ám long) occur on the hypocyst, particularly on the antapical horns Spines may have acuminate or truncated tips and commonly occur in short linear to arcuate groups, incompletely reflecting hypocyst tabulation. The paracingular margins have crests about 2 Ám high. The epicyst is devoid of scattered spines. Two pairs of parasutural crests (one pair on each side of the wide parasulcal region and one pair on the lateral margins) occur along most of the length of the epicyst and converge toward the apex. These crests are up to about 3 Ám high and are distally serrated or denticulate. Additional short crests were sometimes observed at the apex. Seventeen of the 18 specimens found were dorsoventrally compressed.
Affinities:
Head et al., 1989, p.456: Gerlachidium aechmophorum (Benedek, 1972) Benedek and Sarjeant, 1981 emend. Benedek and Sarjeant, 1981, described from the Oligocene of Germany, differs in having parasutural crests that are discontinuous both on the paracingular margins and on the epicyst, and that are higher (8-12 Ám) and less evenly serrated than for C. cristatoserratum.