Back
Diconodinium firmum
Diconodinium firmum Harland, 1973
Now Laciniadinium. Originally Diconodinium, subsequently (and now) Laciniadinium.
Holotype: Harland, 1973, pl.84, fig.8
Locus typicus: S Alberta, Canada
Stratum typicum: Late Campanian
Original diagnosis: Harland, 1973, p. 669
Proximate cyst, commonly fusiform in shape, consisting of autophragm or two wall layers very closely adpressed. Test finely granulate. Epitract extends into an apical horn having a solid distal tip which may be oblate, acuminate, or bifurcate. The antapical horn always acuminate, and hollow throughout. The cingulum conspicuous and takes the form of a slight laevorotatory helicoid. Tabulation not usually seen. Archeopyle precingular of the P type (Evitt 1967), and rounded polygonal in shape.
Original description: Harland, 1973, p.669-670
The granules on the walls are of variable size, usually fairly fine, but always conspicuous. The solid apical tip appears to have a definite structure (Pl. 84, fig. 15). It was often seen to be banded but its exact nature must await further study.
The cingulum is displaced by less than one-quarter of its width. Very little variation was seen in this cyst species except as documented in dimensions and in the nature of the apical tip.
Dimensions. Holotype: Length 42.0 Ám; breadth 29.0 Ám. Range: Length 36.0 (42.7) 50.0 Ám; breadth 18.0 (29.3) 32.0 Ám. Fifty specimens measured, out of a studied population of sixty-four.
Affinities:
Harland, 1973, p. 670: This species is characterized by its shape and the solid structure at the distal extremity of the apical horn. It appears close to Diconodinium rhombiformis Vozzhennikova 1967 but is different in its lack of a distinct tabulation and the lack of small gonal processes in the cingular region. Although the archeopyle was rarely observed the conspicuous nature of plate 3" also suggests that the archeopyle is formed by the loss of this plate. The species has gonyaulacacean affinities with apteodinioid lineage.
Now Laciniadinium. Originally Diconodinium, subsequently (and now) Laciniadinium.
Holotype: Harland, 1973, pl.84, fig.8
Locus typicus: S Alberta, Canada
Stratum typicum: Late Campanian
Original diagnosis: Harland, 1973, p. 669
Proximate cyst, commonly fusiform in shape, consisting of autophragm or two wall layers very closely adpressed. Test finely granulate. Epitract extends into an apical horn having a solid distal tip which may be oblate, acuminate, or bifurcate. The antapical horn always acuminate, and hollow throughout. The cingulum conspicuous and takes the form of a slight laevorotatory helicoid. Tabulation not usually seen. Archeopyle precingular of the P type (Evitt 1967), and rounded polygonal in shape.
Original description: Harland, 1973, p.669-670
The granules on the walls are of variable size, usually fairly fine, but always conspicuous. The solid apical tip appears to have a definite structure (Pl. 84, fig. 15). It was often seen to be banded but its exact nature must await further study.
The cingulum is displaced by less than one-quarter of its width. Very little variation was seen in this cyst species except as documented in dimensions and in the nature of the apical tip.
Dimensions. Holotype: Length 42.0 Ám; breadth 29.0 Ám. Range: Length 36.0 (42.7) 50.0 Ám; breadth 18.0 (29.3) 32.0 Ám. Fifty specimens measured, out of a studied population of sixty-four.
Affinities:
Harland, 1973, p. 670: This species is characterized by its shape and the solid structure at the distal extremity of the apical horn. It appears close to Diconodinium rhombiformis Vozzhennikova 1967 but is different in its lack of a distinct tabulation and the lack of small gonal processes in the cingular region. Although the archeopyle was rarely observed the conspicuous nature of plate 3" also suggests that the archeopyle is formed by the loss of this plate. The species has gonyaulacacean affinities with apteodinioid lineage.