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Gonyaulacysta jurassica var. quadrata
Gonyaulacysta jurassica var. quadrata Kumar, 1986
Holotype: Kumar, 1986, pl.1, fig.6
Locus typicus: Kachchh, India
Stratum typicum: Kimmeridgian-Tithonian
Original diagnosis: Kumar, 1986, p.388
A delphicavate variety of G. jurassica subsp. jurassica Sarjeant (1982) whose hypopericoel has a broad, rounded quadrangular opisthopyle with either concave or straight basal margins.
Original description: Kumar, 1986, p.388
A variety of Gonyaulacysta jurassica subsp. jurassica Sarjeant (1982), which is typically delphicavate. The hypopericoel extends up to the paracingulum and its base is always broad and more or less rounded quadrangular. The bases of the four sides of the hypopericoel show different degrees of concavity. They may also be straight, and the maximum degree of concavity is always on the dorsal side (Fig.3).
Dimension: Based on ten specimens. Cyst length = 113--137 Ám. Cyst width = 55--77 Ám. Horn length = 22--30 Ám. Archaeopyle length = 38.5-49.5 Ám. Archaeopyle width = 20--30 Ám. Maximum diameter of opisthopyle = 33--38.5 Ám.
Affinities:
Kumar, 1986, p.388: G. jurassic subsp. jurassica var. quadrata is quite similar to Psaligonyaulax dualis Brideaux and Fisher, 1976 (which is considered a junior synonym of G. jurassica by Sarjeant, 1982), but it differs in having a broader, rounded quadrangular opisthopyle with straight or concave basal margins. The present variety is also larger than Psaligonyaulax dualis.
Holotype: Kumar, 1986, pl.1, fig.6
Locus typicus: Kachchh, India
Stratum typicum: Kimmeridgian-Tithonian
Original diagnosis: Kumar, 1986, p.388
A delphicavate variety of G. jurassica subsp. jurassica Sarjeant (1982) whose hypopericoel has a broad, rounded quadrangular opisthopyle with either concave or straight basal margins.
Original description: Kumar, 1986, p.388
A variety of Gonyaulacysta jurassica subsp. jurassica Sarjeant (1982), which is typically delphicavate. The hypopericoel extends up to the paracingulum and its base is always broad and more or less rounded quadrangular. The bases of the four sides of the hypopericoel show different degrees of concavity. They may also be straight, and the maximum degree of concavity is always on the dorsal side (Fig.3).
Dimension: Based on ten specimens. Cyst length = 113--137 Ám. Cyst width = 55--77 Ám. Horn length = 22--30 Ám. Archaeopyle length = 38.5-49.5 Ám. Archaeopyle width = 20--30 Ám. Maximum diameter of opisthopyle = 33--38.5 Ám.
Affinities:
Kumar, 1986, p.388: G. jurassic subsp. jurassica var. quadrata is quite similar to Psaligonyaulax dualis Brideaux and Fisher, 1976 (which is considered a junior synonym of G. jurassica by Sarjeant, 1982), but it differs in having a broader, rounded quadrangular opisthopyle with straight or concave basal margins. The present variety is also larger than Psaligonyaulax dualis.