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Rhaetogonyaulax tortuosa
Rhaetogonyaulax tortuosa Fisher and Van Helden, 1979
Tax. jr. synonym of Rhaetogonyaulax rhaetica (Sarjeant, 1963) Loeblich Jr
and Loeblich III, 1968, according to Below, 1987.
Holotype: Fisher and Van Helden 1979, pl.4, fig.4-6
Locus typicus: Ellef Ringnes Island, Canadian Arctic Archipelago
Stratum typicum: Karnian-Rhaetian
Original diagnosis: Fisher and Van Helden, 1979, p. 274
Same as for the genus with the following additional description: The cyst wall is scabrate to reticulate without further ornamentation. Possesses one elongated apical and one elongated antapical horn. The cyst is symmetrically acutely biconical. Archaeopyle type is A4" + 5I with the intercalary paraplates la and/or 5a (opercular pieces) commonly adherent to the cyst. Epicyst characteristically distorted. Apical horn is bent toward the dorsal side after loss of the operculum.
Dimensions: Holotype: Length 92µm, width 46 µm.
Paratypes: (15 specimens measured) length 72-103 µm, width 41-52µm.
Affinities:
Fisher and Van Helden, 1979, p. 274: R. tortuosa is morphologically distinct from R. testacea in being generally larger, more acutely biconical and in possessing more distinct and slightly longer apical and antapical horns. The lack of spinose ornamentation readily distinguishes it from R. uncinata. It differs also from R. rhaetica in having a A4"+ 5I archaeopyle rather than a (6A5I) archaeopyle (Text-Figures 3A, 3B).
Tax. jr. synonym of Rhaetogonyaulax rhaetica (Sarjeant, 1963) Loeblich Jr
and Loeblich III, 1968, according to Below, 1987.
Holotype: Fisher and Van Helden 1979, pl.4, fig.4-6
Locus typicus: Ellef Ringnes Island, Canadian Arctic Archipelago
Stratum typicum: Karnian-Rhaetian
Original diagnosis: Fisher and Van Helden, 1979, p. 274
Same as for the genus with the following additional description: The cyst wall is scabrate to reticulate without further ornamentation. Possesses one elongated apical and one elongated antapical horn. The cyst is symmetrically acutely biconical. Archaeopyle type is A4" + 5I with the intercalary paraplates la and/or 5a (opercular pieces) commonly adherent to the cyst. Epicyst characteristically distorted. Apical horn is bent toward the dorsal side after loss of the operculum.
Dimensions: Holotype: Length 92µm, width 46 µm.
Paratypes: (15 specimens measured) length 72-103 µm, width 41-52µm.
Affinities:
Fisher and Van Helden, 1979, p. 274: R. tortuosa is morphologically distinct from R. testacea in being generally larger, more acutely biconical and in possessing more distinct and slightly longer apical and antapical horns. The lack of spinose ornamentation readily distinguishes it from R. uncinata. It differs also from R. rhaetica in having a A4"+ 5I archaeopyle rather than a (6A5I) archaeopyle (Text-Figures 3A, 3B).