Back
Trabeculidium quinquetrum
Trabeculodinium quinquetrum Duxbury, 1980
Originally (and now) Trabeculidium, subsequently Nematosphaeropsis. Stover and Williams, 1987 transferred this species to Nematosphaeropsis Deflandre and Cookson, 1955. Lentin and Williams, 1993 retain the species in Trabeculidium, following Sarjeant, 1989, who maintained that Trabeculidium is a separate genus.
Holotype: Duxbury, 1980, pl.9, fig.2
Locus typicus: Speeton Clay, Speeton, England
Stratum typicum: Barremian
Original diagnosis: Duxbury, 1980, p.132
A species of dinoflagellate cyst whose main body is pentagonal in lateral view due to its having a distinctly triangular epicyst and sharp-angled, trapeziform hypocyst. Trifurcate gonal and bifurcate parasutural processes are present and these vary in length so that despite the polyhedral shape of the main body, the cyst as a whole is spheroidal. Both gonal and parasutural processes are proximally unconnected and distally joined by solid, thin trabeculae. Each parasutural line is distally reflected by two trabeculae. The archeopyle is precingular, formed by detachment of paraplate 3".
Observed Dimensions: Holotype--76 x 76 µm. Overall--81 (74) 68 x 78 (70) 59 µm.
Originally (and now) Trabeculidium, subsequently Nematosphaeropsis. Stover and Williams, 1987 transferred this species to Nematosphaeropsis Deflandre and Cookson, 1955. Lentin and Williams, 1993 retain the species in Trabeculidium, following Sarjeant, 1989, who maintained that Trabeculidium is a separate genus.
Holotype: Duxbury, 1980, pl.9, fig.2
Locus typicus: Speeton Clay, Speeton, England
Stratum typicum: Barremian
Original diagnosis: Duxbury, 1980, p.132
A species of dinoflagellate cyst whose main body is pentagonal in lateral view due to its having a distinctly triangular epicyst and sharp-angled, trapeziform hypocyst. Trifurcate gonal and bifurcate parasutural processes are present and these vary in length so that despite the polyhedral shape of the main body, the cyst as a whole is spheroidal. Both gonal and parasutural processes are proximally unconnected and distally joined by solid, thin trabeculae. Each parasutural line is distally reflected by two trabeculae. The archeopyle is precingular, formed by detachment of paraplate 3".
Observed Dimensions: Holotype--76 x 76 µm. Overall--81 (74) 68 x 78 (70) 59 µm.