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Pterodinium aliferum
Pterodinium aliferum Eisenack, 1958a, p.395–396, pl.24, fig.6; text-fig.6. Emendation: Sarjeant, 1985a, p.72–74 — however, see Jan du Chêne et al. (1986a, p.273).
Jan du Chene et al., 1986 did not accept the emendation of this species by Sarjeant ,1985
Holotype: Eisenack, 1958, pl.24, fig.6, text-fig.6; Sarjeant, 1985, pl.5, fig.1-2, text-fig. 5; Jan du Chene et al., 1986, pl.87, figs.1-6
Locus typicus: borehole at Marne, Feld Heide, Germany
Stratum typicum: Late Aptian
Original diagnosis: Eisenack, 1958, pp.395-396
Shell oval, tabulate with spiral girdle and proportionately narrow fields, with more or less parallel boundaries running in the direction of the long axis. The field boundaries are marked by strongly developed, often strongly denticulate crests. In particular the median level is surrounded by a broad seem, usually with few denticles. A pylome is developed dorsally on the epivalve beneath the apex.
Emended diagnosis: Sarjeant, 1985, p.73
Proximochorate, murochorate cysts of moderate size, ovoidal to broadly ellipsoidal, without horns. Boundaries of principal paraplates marked by high crests (c.20% of the central-body breadth), which may be sustained by gonal spines of lesser height or may lack such support. Crests variably and irregularly perforate or fenestrate, with entire, undulate, machicolate or rhodanate distal margins; the nature of the distal margin varies on a single specimen and between individuals. Lesser crests subdivide the cingulum and low lines demarcate sulcal paraplates. Surface of phragma granular.
Paratabulation ?0pr, 4", 6", 6c, 6""", 2p, 1pv, 1"""", ?7s. Paraplates 4" and 6"" are both roughly quadrate, of similar size and with a long mutual boundary intersecting that of 1" almost at the junction of the latter with the sulcus. Paraplate 1""" reduced and quadrate, accommodating an elongate 1p; 6""" is reduced to make room for paraplate 2p; antapical paraplate rather small and slightly inclined to the ventral surface. Cingulum broad and only feebly laevorotatory. Sulcus broad and short, occupying only the central portion of the ventral surface and divided into one anterior, four median and two posterior paraplates.
Archaeopyle single-plate precingular (type P), formed by loss of paraplate 3".
Jan du Chene et al., 1986 did not accept the emendation of this species by Sarjeant ,1985
Holotype: Eisenack, 1958, pl.24, fig.6, text-fig.6; Sarjeant, 1985, pl.5, fig.1-2, text-fig. 5; Jan du Chene et al., 1986, pl.87, figs.1-6
Locus typicus: borehole at Marne, Feld Heide, Germany
Stratum typicum: Late Aptian
Original diagnosis: Eisenack, 1958, pp.395-396
Shell oval, tabulate with spiral girdle and proportionately narrow fields, with more or less parallel boundaries running in the direction of the long axis. The field boundaries are marked by strongly developed, often strongly denticulate crests. In particular the median level is surrounded by a broad seem, usually with few denticles. A pylome is developed dorsally on the epivalve beneath the apex.
Emended diagnosis: Sarjeant, 1985, p.73
Proximochorate, murochorate cysts of moderate size, ovoidal to broadly ellipsoidal, without horns. Boundaries of principal paraplates marked by high crests (c.20% of the central-body breadth), which may be sustained by gonal spines of lesser height or may lack such support. Crests variably and irregularly perforate or fenestrate, with entire, undulate, machicolate or rhodanate distal margins; the nature of the distal margin varies on a single specimen and between individuals. Lesser crests subdivide the cingulum and low lines demarcate sulcal paraplates. Surface of phragma granular.
Paratabulation ?0pr, 4", 6", 6c, 6""", 2p, 1pv, 1"""", ?7s. Paraplates 4" and 6"" are both roughly quadrate, of similar size and with a long mutual boundary intersecting that of 1" almost at the junction of the latter with the sulcus. Paraplate 1""" reduced and quadrate, accommodating an elongate 1p; 6""" is reduced to make room for paraplate 2p; antapical paraplate rather small and slightly inclined to the ventral surface. Cingulum broad and only feebly laevorotatory. Sulcus broad and short, occupying only the central portion of the ventral surface and divided into one anterior, four median and two posterior paraplates.
Archaeopyle single-plate precingular (type P), formed by loss of paraplate 3".