Back
Psaligonyaulax australica
Psaligonyaulax australica Cookson and Eisenack, 1982
Taxonomic senior synonym: Psaligonyaulax (as and now Gonyaulacysta) dualis, according to Brenner (1988, p.54).
Taxonomic senior synonym: Scriniodinium? ceratophorum, according to Jan du Chêne et al. (1986a, p.266).
Holotype: Cookson and Eisenack, 1982, pl.2, fig.14; lost according to Jan du Chêne et al., 1986
Age: Oxfordian-early Kimmeridgian
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1982] (translated from German):
Psaligonyaulax australica n. sp.
Plate 2, Figs. 13-15
Type: The specimen shown on Plate 2, Fig. 14, preserved in specimen Cape Range No. 2.
Locus typicus and stratum typicum: Cape Range. Dingo Claystone (upper portion), Wapet's Well No. 2 between 3970 and 3991 ft. Oxfordian to Lower Kimeridgian. Exmouth Gulf area of Carnarvon Basin, Western Australia.
Diagnosis: A Psaligonyaulax that closely resembles Ps. apatela, but differs in that the antapical appendage, which in Ps. apatela is developed as a four-sided appendage, is either only vaguely present or completely absent in Ps. australica, so that Ps. australica then has a rounded antapical end. The periphragm is thin, the surface smooth. No wainscoting is discernible. The endophragm is also thin-walled and delicate, often difficult to identify. The apical projection, which is usually distinct in Ps. apatela, is also present, but not always distinct.
The apical horn, as in Ps. apatela, is well defined; it is cylindrical to slightly conical and blunt at the end.
The archaeopyle is horseshoe-shaped and sometimes very elongated; it extends from the girdle region almost to the base of the apical horn.
Dimensions: Holotype: approx. 140 x 76 μ long, the remaining specimens measure approx. 109 x 6 μ, 114 x 78 μ, and 128 x 76 μ.
Relationships: Ps. australica is very similar to Psaligonyanlax sp., briefly described by GrTMEZ 1970, p. 304, and illustrated in Plate 3, Fig. 6, and in text fig. 30, except that it is smaller at 70 μ long.
There is also a similarity to "Gonyaulacysta jurassica" in Pocock (1972, p. 197; pl. 22 Fig. 9), which is certainly not G. jurasica: Both forms share the same overall outline.
Our species differs from Gonyaulacysta jurassica in its more slender form, the absence of plating, and the serrations on the lateral margins.
Occurrence: See above under Locus typicus.
Taxonomic senior synonym: Psaligonyaulax (as and now Gonyaulacysta) dualis, according to Brenner (1988, p.54).
Taxonomic senior synonym: Scriniodinium? ceratophorum, according to Jan du Chêne et al. (1986a, p.266).
Holotype: Cookson and Eisenack, 1982, pl.2, fig.14; lost according to Jan du Chêne et al., 1986
Age: Oxfordian-early Kimmeridgian
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1982] (translated from German):
Psaligonyaulax australica n. sp.
Plate 2, Figs. 13-15
Type: The specimen shown on Plate 2, Fig. 14, preserved in specimen Cape Range No. 2.
Locus typicus and stratum typicum: Cape Range. Dingo Claystone (upper portion), Wapet's Well No. 2 between 3970 and 3991 ft. Oxfordian to Lower Kimeridgian. Exmouth Gulf area of Carnarvon Basin, Western Australia.
Diagnosis: A Psaligonyaulax that closely resembles Ps. apatela, but differs in that the antapical appendage, which in Ps. apatela is developed as a four-sided appendage, is either only vaguely present or completely absent in Ps. australica, so that Ps. australica then has a rounded antapical end. The periphragm is thin, the surface smooth. No wainscoting is discernible. The endophragm is also thin-walled and delicate, often difficult to identify. The apical projection, which is usually distinct in Ps. apatela, is also present, but not always distinct.
The apical horn, as in Ps. apatela, is well defined; it is cylindrical to slightly conical and blunt at the end.
The archaeopyle is horseshoe-shaped and sometimes very elongated; it extends from the girdle region almost to the base of the apical horn.
Dimensions: Holotype: approx. 140 x 76 μ long, the remaining specimens measure approx. 109 x 6 μ, 114 x 78 μ, and 128 x 76 μ.
Relationships: Ps. australica is very similar to Psaligonyanlax sp., briefly described by GrTMEZ 1970, p. 304, and illustrated in Plate 3, Fig. 6, and in text fig. 30, except that it is smaller at 70 μ long.
There is also a similarity to "Gonyaulacysta jurassica" in Pocock (1972, p. 197; pl. 22 Fig. 9), which is certainly not G. jurasica: Both forms share the same overall outline.
Our species differs from Gonyaulacysta jurassica in its more slender form, the absence of plating, and the serrations on the lateral margins.
Occurrence: See above under Locus typicus.