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Dichadogonyaulax rotunda
Dichadogonyaulax rontunda (Dodekova, 1975) Woolam, 1983
Now Ctenidodinium?. Originally Ctenidodinium subsequently Dichadogonyaulax, thirdly (and now) Ctenidodinium?.
Benson, 1985, questionally retained this species in Ctenidodinium Deflandre, 1938.
Probable tax. sr. synonym of Dichadogonyaulax stauromatos Sarjeant, 1976, according to Dodekova, 1990.
Holotype: Dodekova, 1975, pl.4, figs13-14, text-fig.1
Locus typicus: NE Bulgaria
Stratum typicum: Bathonian
Original description: Dodekova, 1975, p.19: Ctenidodinium rontundum
Spheroidal proximo-chorate cyst, halved by laevorotatory spiral cingulum. Sulcus narrow, extends from the basis of the epitract (near to the cingulum) to the antapex. Tabulation formula 4", 6"", ?c, 6""", 1p, 1"""" (text-fig. 1). Typical feature of the species is that the apical plates 2" and 3" are near or exceed in dimensions the plates of the precingular file--2"", 3"", 6"". The wall is two-layered. The endophragm is thick. The periphragm is thin, foveolate, covered by densely arranged pits. The sutures are marked by short (3 Ám) fenestrate septa (textfig. l, n, c). Distally the septa have slender processes, which briefly bifurcate at their distal ends. More rare are the processes which fork near the base, or in the middle (text-fig.1, c). The septa and the processes on the hypotract are relatively largrer. The processes are perforated to various extent. The archaeopyle is epitractal (type AP).
Affinities:
Dodekova, 1975, p. 20: Ctenidodinium rontundum
The new species differs from the remaining species of the genus by its regular rounded outline, larger dimensions of the body and of the apical plates, foveolate structure of the periphragm, the perforation of the septa and the processes.
Now Ctenidodinium?. Originally Ctenidodinium subsequently Dichadogonyaulax, thirdly (and now) Ctenidodinium?.
Benson, 1985, questionally retained this species in Ctenidodinium Deflandre, 1938.
Probable tax. sr. synonym of Dichadogonyaulax stauromatos Sarjeant, 1976, according to Dodekova, 1990.
Holotype: Dodekova, 1975, pl.4, figs13-14, text-fig.1
Locus typicus: NE Bulgaria
Stratum typicum: Bathonian
Original description: Dodekova, 1975, p.19: Ctenidodinium rontundum
Spheroidal proximo-chorate cyst, halved by laevorotatory spiral cingulum. Sulcus narrow, extends from the basis of the epitract (near to the cingulum) to the antapex. Tabulation formula 4", 6"", ?c, 6""", 1p, 1"""" (text-fig. 1). Typical feature of the species is that the apical plates 2" and 3" are near or exceed in dimensions the plates of the precingular file--2"", 3"", 6"". The wall is two-layered. The endophragm is thick. The periphragm is thin, foveolate, covered by densely arranged pits. The sutures are marked by short (3 Ám) fenestrate septa (textfig. l, n, c). Distally the septa have slender processes, which briefly bifurcate at their distal ends. More rare are the processes which fork near the base, or in the middle (text-fig.1, c). The septa and the processes on the hypotract are relatively largrer. The processes are perforated to various extent. The archaeopyle is epitractal (type AP).
Affinities:
Dodekova, 1975, p. 20: Ctenidodinium rontundum
The new species differs from the remaining species of the genus by its regular rounded outline, larger dimensions of the body and of the apical plates, foveolate structure of the periphragm, the perforation of the septa and the processes.