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Leberidocysta eisenackii
Leberidocysta? eisenackii (Mehrota and Sarjeant, 1984) Lentin and Williams, 1985
Now Platycystidia (Acritarch). Originally Polygonifera, subsequently Leberidocysta?, thirdly (and now) Platycystidia (Acritarch).
Lister and Batten, 1988, questionably included this species in Leberidocysta.
Holotype: Mehrota and Sarjeant, 1984, pl.1, fig.6, text-fig.1c
Locus typicus: Perivadavadi shallow well- 1, Cauvery basin, South India
Stratum typicum: Aptian
Original diagnosis: Mehrota and Sarjeant, 1984, p. 46: Polygonifera eisenackii
Cyst proximate, camocavate. Periblast polygonal-subpolygonal or oval in ambitus, oval in lateral view; endoblast oval to broadly ellipsoidal. Apical horn lacking; a small notch may develop in the apical region, due to periphragm folding. Periphragm thin, delicate; it may be fully, partially or not at all developed and, when present, is typically folded. Endophragm relatively thicker and typically not distorted. Both endophragm and periphragm are smooth or weakly ornamented (reticulate, foveoreticulate, or finely punctate). No parasutural features are present. Archaeopyle apical, (4a)/(4a); peripyle and endopyle are usually distinct. Operculum free or attached. Cingulum indicated by periphragm folding, sometimes distinct and completely developed, in other instances faintly, incompletely or not at all suggested. Typically, no indication of a sulcus is seen other than a poorly marked sulcal notch. A claustrum of variable size and shape may be present in the hypotract.
Dimensions. Holotype (operculum attached); periblast 89x50 Ám; endoblast 68x39 Ám. Paratype a (operculum attached); periblast 55x40 Ám; endoblast 45x32 Ám. Paratype b (operculum attached); periblast 92x63 Ám; endoblast 61x45 Ám. Range" (operculum free); periblast 50x48 Ám to 92x73 Ám, endoblast 40x35 to 61x45 Ám. A single specimen (Pl. 2, fig. 6) measured with periblast partially developed, endoblast complete with attached operculum; endoblast 42x37 Ám.
Affinities:
Mehrota and Sarjeant, 1984, p. 48: Polygonifera eisenackii
This species is readily distinguishable from P. evittii and P. (ex: Hexagonifera) chlamydata by its laevigate to weakly ornamented endoblast. The endoblast ornamentation in P. evittii is scabrate to granulose and that in P. chlamydata is verrucose. The degree of development of the cingulum is variable in P. eisenackii, whereas the cingulum is well developed in P. evittii (Habib,1972, pl.5, figs.1,2) and not developed at all in P. chlamydata (Cookson & Eisenack, 1962, pl. 7, figs. 1-3, 5-8.).
Now Platycystidia (Acritarch). Originally Polygonifera, subsequently Leberidocysta?, thirdly (and now) Platycystidia (Acritarch).
Lister and Batten, 1988, questionably included this species in Leberidocysta.
Holotype: Mehrota and Sarjeant, 1984, pl.1, fig.6, text-fig.1c
Locus typicus: Perivadavadi shallow well- 1, Cauvery basin, South India
Stratum typicum: Aptian
Original diagnosis: Mehrota and Sarjeant, 1984, p. 46: Polygonifera eisenackii
Cyst proximate, camocavate. Periblast polygonal-subpolygonal or oval in ambitus, oval in lateral view; endoblast oval to broadly ellipsoidal. Apical horn lacking; a small notch may develop in the apical region, due to periphragm folding. Periphragm thin, delicate; it may be fully, partially or not at all developed and, when present, is typically folded. Endophragm relatively thicker and typically not distorted. Both endophragm and periphragm are smooth or weakly ornamented (reticulate, foveoreticulate, or finely punctate). No parasutural features are present. Archaeopyle apical, (4a)/(4a); peripyle and endopyle are usually distinct. Operculum free or attached. Cingulum indicated by periphragm folding, sometimes distinct and completely developed, in other instances faintly, incompletely or not at all suggested. Typically, no indication of a sulcus is seen other than a poorly marked sulcal notch. A claustrum of variable size and shape may be present in the hypotract.
Dimensions. Holotype (operculum attached); periblast 89x50 Ám; endoblast 68x39 Ám. Paratype a (operculum attached); periblast 55x40 Ám; endoblast 45x32 Ám. Paratype b (operculum attached); periblast 92x63 Ám; endoblast 61x45 Ám. Range" (operculum free); periblast 50x48 Ám to 92x73 Ám, endoblast 40x35 to 61x45 Ám. A single specimen (Pl. 2, fig. 6) measured with periblast partially developed, endoblast complete with attached operculum; endoblast 42x37 Ám.
Affinities:
Mehrota and Sarjeant, 1984, p. 48: Polygonifera eisenackii
This species is readily distinguishable from P. evittii and P. (ex: Hexagonifera) chlamydata by its laevigate to weakly ornamented endoblast. The endoblast ornamentation in P. evittii is scabrate to granulose and that in P. chlamydata is verrucose. The degree of development of the cingulum is variable in P. eisenackii, whereas the cingulum is well developed in P. evittii (Habib,1972, pl.5, figs.1,2) and not developed at all in P. chlamydata (Cookson & Eisenack, 1962, pl. 7, figs. 1-3, 5-8.).