Back
Hystrichodinium oligacanthum
From Fensome et al., 2019:
Hystrichodinium oligacanthum Deflandre and Cookson, 1955, p.255–257, pl.1, fig.1; text figs. 2–3. Holotype: Deflandre and Cookson, 1955, text-fig.2. Backhouse (1988, p.92) considered Heliodinium (as Hystrichodinium) patriciae and Heliodinium (as Hystrichodinium) voigtii to be possible taxonomic junior synonyms of this species. Hystrichodinium oligacanthum was notvalidly published in Deflandre and Cookson (1954, p.1236) since no description was provided. Age: Albian.
---------------------------------------------------------------------------------------------------
Locus typicus: North-South-Wales, Onepah Station
Original diagnosis: Deflandre and Cookson, 1955, p.256
Theca with rounded poles, epitheca a little larger than the hypotheca, the transverse girdle strongly helicoidal and left-handed with no appendages on its upper rim but 6 or 7 on its lower rim. The horns are long often attaining the length of the theca: there are about 4 or 5 on the upper half of the epitheca and 3 to 4 on the hypotheca, the total number being approximately 14. Certain specimens, perhaps incomplete, have shown 11 or 12. Membrane of theca clearly ornamented.
Dimensions: Holotype: theca, length 47 µm, breadth 42 µm, horns 35-42 µm, total length 117 µm. Another example: length 43 µm, breadth 40 µm, horns 39-44 µm, overall length 106 µm.
Hystrichodinium oligacanthum Deflandre and Cookson, 1955, p.255–257, pl.1, fig.1; text figs. 2–3. Holotype: Deflandre and Cookson, 1955, text-fig.2. Backhouse (1988, p.92) considered Heliodinium (as Hystrichodinium) patriciae and Heliodinium (as Hystrichodinium) voigtii to be possible taxonomic junior synonyms of this species. Hystrichodinium oligacanthum was notvalidly published in Deflandre and Cookson (1954, p.1236) since no description was provided. Age: Albian.
---------------------------------------------------------------------------------------------------
Locus typicus: North-South-Wales, Onepah Station
Original diagnosis: Deflandre and Cookson, 1955, p.256
Theca with rounded poles, epitheca a little larger than the hypotheca, the transverse girdle strongly helicoidal and left-handed with no appendages on its upper rim but 6 or 7 on its lower rim. The horns are long often attaining the length of the theca: there are about 4 or 5 on the upper half of the epitheca and 3 to 4 on the hypotheca, the total number being approximately 14. Certain specimens, perhaps incomplete, have shown 11 or 12. Membrane of theca clearly ornamented.
Dimensions: Holotype: theca, length 47 µm, breadth 42 µm, horns 35-42 µm, total length 117 µm. Another example: length 43 µm, breadth 40 µm, horns 39-44 µm, overall length 106 µm.