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Diconodinium pelliferum
Diconodinium pelliferum (Cookson and Eisenack, 1958) Eisenack and Cookson, 1960; emend. Morgan, 1977
Originally Palaeohystrichophora, subsequently (and now) Diconodinium.
Holotype: Cookson and Eisenack, 1958, pl.10, fig.11; Morgan, 1977, pl.1, fig.7a-b
Locus typicus: Carnavron Basin, W Australia
Stratum typicum: Albian
Original description: Cookson and Eisenack, 1958, p. 39: Palaeohystrichophora pellifera
The theca is broadly fusiform and divided unequally by the transverse girdle; the "epitheca" is terminated by a shortly bifid process, the "hypotheca" by a short pointed process. The surface is densely covered with spines c.1-2.5 Ám long.
Dimensions: Type 85x59 Ám; the "Tertiary" specimen 122x56 Ám.
Emended description: Morgan, 1977, p.128
Ambitus rhomboidal to fusiform, prolonged into a truncate apical horn and a single sharply pointed antapical horn close to the midline. Epicyst larger than hypocyst. Apparent autophragm mostly thin, but may thicken to form a partly solid apical horn and a wholly or partly solid antapical horn. Surface covered with dense, weakly capitate spines 1.0-2.5 Ám long, nontabular. Spines of uniform length over most of cyst, slightly shorter near apical horn. Only indication of paratabulation at the paracingulum, delineated by two slightly raised ridges bearing aligned spines, individual paraplates not visible. Archeopyle not observed, presumed la or IPa as for other species of the genus.
Dimensions: 85-122 Ám long and 56-59 Ám broad.
Affinities:
Morgan, 1977, p. 128: Dense surface ornamentation of 1.0-2.5 Ám long, weakly capitate spines is characteristic of D. pelliferum.
Originally Palaeohystrichophora, subsequently (and now) Diconodinium.
Holotype: Cookson and Eisenack, 1958, pl.10, fig.11; Morgan, 1977, pl.1, fig.7a-b
Locus typicus: Carnavron Basin, W Australia
Stratum typicum: Albian
Original description: Cookson and Eisenack, 1958, p. 39: Palaeohystrichophora pellifera
The theca is broadly fusiform and divided unequally by the transverse girdle; the "epitheca" is terminated by a shortly bifid process, the "hypotheca" by a short pointed process. The surface is densely covered with spines c.1-2.5 Ám long.
Dimensions: Type 85x59 Ám; the "Tertiary" specimen 122x56 Ám.
Emended description: Morgan, 1977, p.128
Ambitus rhomboidal to fusiform, prolonged into a truncate apical horn and a single sharply pointed antapical horn close to the midline. Epicyst larger than hypocyst. Apparent autophragm mostly thin, but may thicken to form a partly solid apical horn and a wholly or partly solid antapical horn. Surface covered with dense, weakly capitate spines 1.0-2.5 Ám long, nontabular. Spines of uniform length over most of cyst, slightly shorter near apical horn. Only indication of paratabulation at the paracingulum, delineated by two slightly raised ridges bearing aligned spines, individual paraplates not visible. Archeopyle not observed, presumed la or IPa as for other species of the genus.
Dimensions: 85-122 Ám long and 56-59 Ám broad.
Affinities:
Morgan, 1977, p. 128: Dense surface ornamentation of 1.0-2.5 Ám long, weakly capitate spines is characteristic of D. pelliferum.