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Escharisphaeridia psilata
Escharisphaeridia psilata Kumar, 1986
Holotype: Kumar, 1986, pl.2, fig.2, text-fig.3
Locus typicus: Kachchh, India
Stratum typicum: Kimmeridgian-Tithonian
Original diagnosis: Kumar, 1986, p.377
Cyst proximate, subsphaerical to ovoidal in dorsal or ventral view, archaeopyle apical, autophragm psilate or finely scabrate. Description: These are proximate, dorsoventrally flattened, ovoidal to subsphaerical cysts. Paratabulation is indicated only by an apical archaeopyle.The operculum can be either free or attached. Sometimes accessory archaeopyle parasutures are present indicating the presence of precingular paraplates. The autophragm is generally psilate but rarely finely scabrate.
Dimension: Based on six specimens. Maximum diameter of cyst 66.0-77.0 Ám. Maximum diameter of archaeopyle 35.0-45.0 Ám.
Affinities:
Kumar, 1986, p.377: E. psilata has psilate or rarely finely scabrate autophragm, whereas E. pocockii (Sarjeant) Erkmen and Sarjeant (1980) has pronounced granular surface, and E. dictydia (Sarjeant) Erkmen and Sarjeant (1980) has dense and minutely reticulate ornamentation.
Poulsen 1996, p. 80
Escharisphaeridia psilata Kumar 1986, Pl. 19, Fig. 3
Eschansphaeridia psilata Kumar, 1986, p. 383-385, pl. 2, fig. 3.
Escharisphaeridia laevigata Smelror, 1988, p. 152-153, figs. 10G-H.
Escharisphaeridia nuda Prauss, 1989, p. 33, pl. 10, figs. 2-3, text-fig. 10.
Escharisphaeridia enayi Courtinat, 1989, p. 181, pl. 23, fig. 6.
Dinocyst sp. A. Woollam, 1980, p.250, pl. 1, figs. 1,4.
Escharisphaeridia sp. Riding et al., 1985, p.156, pl. 5, fig. 8.
Escharisphaeridia sp. SA. Smelror, 1988, p. 288, pl. 4, fig. 5.
Remarks. Escharisphaeridia psilata was described as a species with a psilate or finely scabrate autophragm. Escharisphaeridia laevigata, E. enayi, and E. nuda are similar in overall morphology to E. psilata, all having a psilate autophragm. The specimens studied by Smelror (1988) using SEM had no indication of surface ornamentation. The three mentioned species are considered to be taxonomic junior synonyms of E. psilata. Smelror (1988) also regarded the three unnamed species listed here as conspecific to E. Iaevigata.
Occurrences. Middle Jurassic of Denmark. Middle Bajocian to Late Callovian of north-western Germany. Late Bathonian to Late Oxfordian of southern France, Britain, East Greenland, Svalbard and Franz Josef Land (Arctic CIS). Early Kimmeridigian to Tithonian of Kachchh, India (Kumar 1986; Smelror, 1988; Prauss, 1989; Riding et al., 1985; Courtinat, 1989).
Holotype: Kumar, 1986, pl.2, fig.2, text-fig.3
Locus typicus: Kachchh, India
Stratum typicum: Kimmeridgian-Tithonian
Original diagnosis: Kumar, 1986, p.377
Cyst proximate, subsphaerical to ovoidal in dorsal or ventral view, archaeopyle apical, autophragm psilate or finely scabrate. Description: These are proximate, dorsoventrally flattened, ovoidal to subsphaerical cysts. Paratabulation is indicated only by an apical archaeopyle.The operculum can be either free or attached. Sometimes accessory archaeopyle parasutures are present indicating the presence of precingular paraplates. The autophragm is generally psilate but rarely finely scabrate.
Dimension: Based on six specimens. Maximum diameter of cyst 66.0-77.0 Ám. Maximum diameter of archaeopyle 35.0-45.0 Ám.
Affinities:
Kumar, 1986, p.377: E. psilata has psilate or rarely finely scabrate autophragm, whereas E. pocockii (Sarjeant) Erkmen and Sarjeant (1980) has pronounced granular surface, and E. dictydia (Sarjeant) Erkmen and Sarjeant (1980) has dense and minutely reticulate ornamentation.
Poulsen 1996, p. 80
Escharisphaeridia psilata Kumar 1986, Pl. 19, Fig. 3
Eschansphaeridia psilata Kumar, 1986, p. 383-385, pl. 2, fig. 3.
Escharisphaeridia laevigata Smelror, 1988, p. 152-153, figs. 10G-H.
Escharisphaeridia nuda Prauss, 1989, p. 33, pl. 10, figs. 2-3, text-fig. 10.
Escharisphaeridia enayi Courtinat, 1989, p. 181, pl. 23, fig. 6.
Dinocyst sp. A. Woollam, 1980, p.250, pl. 1, figs. 1,4.
Escharisphaeridia sp. Riding et al., 1985, p.156, pl. 5, fig. 8.
Escharisphaeridia sp. SA. Smelror, 1988, p. 288, pl. 4, fig. 5.
Remarks. Escharisphaeridia psilata was described as a species with a psilate or finely scabrate autophragm. Escharisphaeridia laevigata, E. enayi, and E. nuda are similar in overall morphology to E. psilata, all having a psilate autophragm. The specimens studied by Smelror (1988) using SEM had no indication of surface ornamentation. The three mentioned species are considered to be taxonomic junior synonyms of E. psilata. Smelror (1988) also regarded the three unnamed species listed here as conspecific to E. Iaevigata.
Occurrences. Middle Jurassic of Denmark. Middle Bajocian to Late Callovian of north-western Germany. Late Bathonian to Late Oxfordian of southern France, Britain, East Greenland, Svalbard and Franz Josef Land (Arctic CIS). Early Kimmeridigian to Tithonian of Kachchh, India (Kumar 1986; Smelror, 1988; Prauss, 1989; Riding et al., 1985; Courtinat, 1989).