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Rottnestia wetzelii
Rottnestia wetzelii (Deflandre, 1937b, p.65, pl.11 [al. pl.8], figs.6,8) Slimani, 1994, p.59.
Originally Hystrichosphaera, subsequently Hystrichosphaeropsis (combination not validly published), thirdly Spiniferites, fourthly (and now) Rottnestia.
Taxonomic junior synonym: Hystrichosphaeropsis forficata (name not validly published), according to Slimani (2001a, p.194).
Holotype: Deflandre, 1937b, pl.11 (al. pl.8), figs.6,8.
Age: Senonian.
Emended description: Schioler et al. 1997, p. 89-90
Skolochorate bicavate cyst. The periphragm is smooth and angular, the endophragm is smooth and ovoidal and sometimes has an apical protrusion. The two phragms are separated by two well developed boxshaped pericoels in apical and antapical positions. As the epicystal pericoel is offset from the long axis towards the ventral side, the cyst has an asymmetric appearance in lateral view (Plate III, 17), but is subrectangular in ambital view. The periphragm bears gonal and intergonal processes. The processes are distally trifurcate or bifurcate and are joined proximally by low parasutural septa with irregularly serrate to undulate crests. The length of the processes varies on a specimen: the processes located where the peri- and endophragms are in contact (i.e., the adcingular area) are 15-20 µm, the processes located on the epi- and hypocystal pericoels are 8-10 ,um. The paratabulation is expressed clearly by low septae and has the formula: 3-4", 6", 6c, 5-6"", 1p, 1"". The paracingulum is indicated by low parasutural septate ridges. The parasulcus is indicated by a smooth elongate subrectangular area. The archeopyle is precingular, type P(3). The operculum is usually free.
Dimensions (in µm, 14 specimens measured): length of pericyst, 80 (96) 113; width of pericyst, 69 (78) 88; length of endocyst, 41 (47) 55; width of endocyst, 47 (49) 58.
Discussion: Schioler et al. 1997, p. 90
The description of Rottnestia wetzelii subsp. wetzelii is emended herein to specify the position of the epicystal pericoel which is offset from the long axis towards the ventral side of the cyst. The average size of the pericyst in the specimens from the ENCI Quarry is larger than those given by Slimani (1994); in our opinion, however, there is no doubt about the identity, judged from the photographs and synonomy list provided by Slimani (1994).
Stratigraphic occurrence: Previous; Coniacian-Maastrichtian in northwestern Europe, Maastrichtian in New Jersey. ENCI section; rare in the Lixhe members, extremely rare above.
Originally Hystrichosphaera, subsequently Hystrichosphaeropsis (combination not validly published), thirdly Spiniferites, fourthly (and now) Rottnestia.
Taxonomic junior synonym: Hystrichosphaeropsis forficata (name not validly published), according to Slimani (2001a, p.194).
Holotype: Deflandre, 1937b, pl.11 (al. pl.8), figs.6,8.
Age: Senonian.
Emended description: Schioler et al. 1997, p. 89-90
Skolochorate bicavate cyst. The periphragm is smooth and angular, the endophragm is smooth and ovoidal and sometimes has an apical protrusion. The two phragms are separated by two well developed boxshaped pericoels in apical and antapical positions. As the epicystal pericoel is offset from the long axis towards the ventral side, the cyst has an asymmetric appearance in lateral view (Plate III, 17), but is subrectangular in ambital view. The periphragm bears gonal and intergonal processes. The processes are distally trifurcate or bifurcate and are joined proximally by low parasutural septa with irregularly serrate to undulate crests. The length of the processes varies on a specimen: the processes located where the peri- and endophragms are in contact (i.e., the adcingular area) are 15-20 µm, the processes located on the epi- and hypocystal pericoels are 8-10 ,um. The paratabulation is expressed clearly by low septae and has the formula: 3-4", 6", 6c, 5-6"", 1p, 1"". The paracingulum is indicated by low parasutural septate ridges. The parasulcus is indicated by a smooth elongate subrectangular area. The archeopyle is precingular, type P(3). The operculum is usually free.
Dimensions (in µm, 14 specimens measured): length of pericyst, 80 (96) 113; width of pericyst, 69 (78) 88; length of endocyst, 41 (47) 55; width of endocyst, 47 (49) 58.
Discussion: Schioler et al. 1997, p. 90
The description of Rottnestia wetzelii subsp. wetzelii is emended herein to specify the position of the epicystal pericoel which is offset from the long axis towards the ventral side of the cyst. The average size of the pericyst in the specimens from the ENCI Quarry is larger than those given by Slimani (1994); in our opinion, however, there is no doubt about the identity, judged from the photographs and synonomy list provided by Slimani (1994).
Stratigraphic occurrence: Previous; Coniacian-Maastrichtian in northwestern Europe, Maastrichtian in New Jersey. ENCI section; rare in the Lixhe members, extremely rare above.