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Laciniadinium inflatum
Laciniadinium? inflatum (Eisenack and Cookson, 1960) Morgan, 1977; Emendation: Morgan, 1977, p.136, Laciniadinium? inflatum.
Originally Diconodinium, subsequently (and now) Laciniadinium?.
Morgan, 1977, questionably included this species in Laciniadinium.
Holotype: Eisenack and Cookson, 1960, pl.1, fig.13; Morgan, 1977, pl.2, figs.5a-c
Locus typicus: N of Gingin, W Australia
Stratum typicum: Late Albian-Cenomanian
Original description: Eisenack and Cookson, 1960, p. 4: Diconodinium inflatum
Shape broadly oval in outline, epitheca longer than hypotheca and terminated by a rather short, hollow, bifid process, hypotheca with a short spine. Shell-membrane two-layered, outer layer ornamented with rather widely-spaced spinules which tent to be arranged in longitudinal rows and to project slightly beyond the surface in optical section; region of "longitudinal furrow" smooth, lines bounding it clearly defined.
Dimensions: Type 88 Ám long, 67 Ám broad. Range 80-95 Ám long, 52-67 Ám broad.
Emended description: Morgan, 1977, p. 136
Pericyst ambitus subcircular, with short truncate apical horn, and short sharp single antapical horn located close to midline. Endocyst ambitus subcircular. Small pericoels developed in the vicinity of the horns, slight ambital pericoel (2-3 Ám wide) developed. Epicyst slightly larger than hypocyst. Periphragm thin, bearing sparse, 1 Ám, nontabular granules. Pericingulum delineated by two slightly raised parasutural ridges, planar. Perisulcus outlined by slightly raised parasutural ridge, extends almost to antapex, individual paraplates not distinguishable. Endophragm psilate. Periarcheopyle apparently (3I3P)a (pl. 2, fig. 5b,c). Endoarcheopyle not observed.
Dimensions: 80-95 Ám long and 52-76 Ám broad.
Affinities:
Morgan, 1977, p. 136: If the wall separation in. L. inflatum has been chemically induced, L. inflatum may be a senior synonym of L. orbiculatum; both have a subcircular ambitus and sparse, nontabular, 1.0Ám granulation; the former differs by being doublewalled, and by having longer horns. Laciniadinium tenuistriatum (Eisenack and Cookson 1960) has a subcircular ambitus and dense aligned granules. Laciniadinium biconiculum Mclntyre 1975 differs by having a rhomboidal ambitus and bearing fine periphragm granules and ridges.
Originally Diconodinium, subsequently (and now) Laciniadinium?.
Morgan, 1977, questionably included this species in Laciniadinium.
Holotype: Eisenack and Cookson, 1960, pl.1, fig.13; Morgan, 1977, pl.2, figs.5a-c
Locus typicus: N of Gingin, W Australia
Stratum typicum: Late Albian-Cenomanian
Original description: Eisenack and Cookson, 1960, p. 4: Diconodinium inflatum
Shape broadly oval in outline, epitheca longer than hypotheca and terminated by a rather short, hollow, bifid process, hypotheca with a short spine. Shell-membrane two-layered, outer layer ornamented with rather widely-spaced spinules which tent to be arranged in longitudinal rows and to project slightly beyond the surface in optical section; region of "longitudinal furrow" smooth, lines bounding it clearly defined.
Dimensions: Type 88 Ám long, 67 Ám broad. Range 80-95 Ám long, 52-67 Ám broad.
Emended description: Morgan, 1977, p. 136
Pericyst ambitus subcircular, with short truncate apical horn, and short sharp single antapical horn located close to midline. Endocyst ambitus subcircular. Small pericoels developed in the vicinity of the horns, slight ambital pericoel (2-3 Ám wide) developed. Epicyst slightly larger than hypocyst. Periphragm thin, bearing sparse, 1 Ám, nontabular granules. Pericingulum delineated by two slightly raised parasutural ridges, planar. Perisulcus outlined by slightly raised parasutural ridge, extends almost to antapex, individual paraplates not distinguishable. Endophragm psilate. Periarcheopyle apparently (3I3P)a (pl. 2, fig. 5b,c). Endoarcheopyle not observed.
Dimensions: 80-95 Ám long and 52-76 Ám broad.
Affinities:
Morgan, 1977, p. 136: If the wall separation in. L. inflatum has been chemically induced, L. inflatum may be a senior synonym of L. orbiculatum; both have a subcircular ambitus and sparse, nontabular, 1.0Ám granulation; the former differs by being doublewalled, and by having longer horns. Laciniadinium tenuistriatum (Eisenack and Cookson 1960) has a subcircular ambitus and dense aligned granules. Laciniadinium biconiculum Mclntyre 1975 differs by having a rhomboidal ambitus and bearing fine periphragm granules and ridges.