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Systematophora placacantha var. curta
Systematophora placacantha var. curta (Matsuoka and Bujak, 1988) Strauss and Lund, 1992
NOW Systematophora? curta. Originally Systematophora curta, subsequently (and now) Systematophora? curta, thirdly Systematophora placacantha var. curta.
Holotype: Matsuoka and Bujak, 1988, pl.15, fig.9
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Navarin Basin COST No. 1 Well, 6660-6750ft, Navarin Basin, Bering Sea
Stratum typicum: Heteraulacacysta campanula Zone; late Oligocene to early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.85: Systematophora cruta
Intermediate subspherical proximochorate cyst with slight polar compression. Cyst surface finely granulate. Paratabulation represented by penitabular process complexes as 4", 6", 6c, 6""", 1p(?), 1"""", 0s. Penitabular complexes variable; apical area having incomplete annulate types with two to four small processes on each paraplate; pre- and postcingular areas with six box-like penitabular complexes but the 1""" process complex somewhat reduced and small; antapical area possessing one large annulate complex. Processes short, solid, wide and tubiform to buccinate with simple flat distal extremities. Most of bases of the adjacent processes not connecting and reduced. Paracingulum delineated by six rectilinear complexes and approximately circular; parasulcus with process complexes. Archeopyle tetratabular, apical, formed by the loss of four paraplates.
Original description: Matsuoka and Bujak, 1988, p.85: Systematophora cruta
The cyst body is subspherical, without horns at the apex and antapex, but sometimes has processes at the apex that are longer than the other processes. The cyst wall consists of two layers which are strongly adpressed over most of the cyst body. The penitabular complexes are annulate or rectilinear. The processes are usually wide and short, with slightly recurved or simple distal tips. Three apical penitabular complexes are present, but one of these probably includes the 1" and 4" paraplates based on its shape (Text-fig. 21). The first postcingular process complex is very small. The paracingulum is represented by approximately six rectilinear ridges, and is almost circular. The parasulcus lacks processes. The archeopyle is apical and is formed by the loss of all of the apical paraplates.
Dimensions: Holotype; cyst diameter 48 µm, length of processes 6-7 µm. Range; cyst diameter 43-53 µm, length of processes 5-9 µm, diameter of free operculum, 35 x 38 µm-41 x 39 µm. Number of specimens measured; 8.
Supplemental description: Strauss and Lund, 1993, p.173
A variety of Systematophora placacantha with variable expression of penitabular annular ridges and more or less complete process complexes (compare Matsuoka and Bujak, 1988, p. 85). The processes are characteristically reduced in length (4 ... 8 µm, max. 10 µm), taeniate, relatively broad and membranous, distally slightly expanded and partially confluent with adjoining processes to more or less complete annular, penitabular, scalloped crests.
The type species of Matsuoka and Bujak (1988) is very similar to the Papendorf-individuals, differing only slightly in apparently showing no laterally confluent processes.
Archaeopyle opening and paratabulation pattern, as well as central body size, coincide with S. placacantha.
Affinities:
Matsuoka and Bujak, 1988, p. 85: Systematophora cruta
Systematophora cruta is characterized by the possession of well-developed penitabular complexes and processes that are mostly solid, wide, cylindrical to tubiform, with simple or recurved distal extremities. The species differs from other species of Systematophora because of its short processes.
Strauss and Lund, 1988, p.173: This variety is an extreme representative of the very broad range of variational types accommodated by Systematophora placacantha. Consequently, all transitional types between S. placacantha s. s. and var. curta are known to occur.
The variety curta is always present in Northern German samples with rich and morphologically diverse populations of S. placacantha.
NOW Systematophora? curta. Originally Systematophora curta, subsequently (and now) Systematophora? curta, thirdly Systematophora placacantha var. curta.
Holotype: Matsuoka and Bujak, 1988, pl.15, fig.9
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Navarin Basin COST No. 1 Well, 6660-6750ft, Navarin Basin, Bering Sea
Stratum typicum: Heteraulacacysta campanula Zone; late Oligocene to early Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.85: Systematophora cruta
Intermediate subspherical proximochorate cyst with slight polar compression. Cyst surface finely granulate. Paratabulation represented by penitabular process complexes as 4", 6", 6c, 6""", 1p(?), 1"""", 0s. Penitabular complexes variable; apical area having incomplete annulate types with two to four small processes on each paraplate; pre- and postcingular areas with six box-like penitabular complexes but the 1""" process complex somewhat reduced and small; antapical area possessing one large annulate complex. Processes short, solid, wide and tubiform to buccinate with simple flat distal extremities. Most of bases of the adjacent processes not connecting and reduced. Paracingulum delineated by six rectilinear complexes and approximately circular; parasulcus with process complexes. Archeopyle tetratabular, apical, formed by the loss of four paraplates.
Original description: Matsuoka and Bujak, 1988, p.85: Systematophora cruta
The cyst body is subspherical, without horns at the apex and antapex, but sometimes has processes at the apex that are longer than the other processes. The cyst wall consists of two layers which are strongly adpressed over most of the cyst body. The penitabular complexes are annulate or rectilinear. The processes are usually wide and short, with slightly recurved or simple distal tips. Three apical penitabular complexes are present, but one of these probably includes the 1" and 4" paraplates based on its shape (Text-fig. 21). The first postcingular process complex is very small. The paracingulum is represented by approximately six rectilinear ridges, and is almost circular. The parasulcus lacks processes. The archeopyle is apical and is formed by the loss of all of the apical paraplates.
Dimensions: Holotype; cyst diameter 48 µm, length of processes 6-7 µm. Range; cyst diameter 43-53 µm, length of processes 5-9 µm, diameter of free operculum, 35 x 38 µm-41 x 39 µm. Number of specimens measured; 8.
Supplemental description: Strauss and Lund, 1993, p.173
A variety of Systematophora placacantha with variable expression of penitabular annular ridges and more or less complete process complexes (compare Matsuoka and Bujak, 1988, p. 85). The processes are characteristically reduced in length (4 ... 8 µm, max. 10 µm), taeniate, relatively broad and membranous, distally slightly expanded and partially confluent with adjoining processes to more or less complete annular, penitabular, scalloped crests.
The type species of Matsuoka and Bujak (1988) is very similar to the Papendorf-individuals, differing only slightly in apparently showing no laterally confluent processes.
Archaeopyle opening and paratabulation pattern, as well as central body size, coincide with S. placacantha.
Affinities:
Matsuoka and Bujak, 1988, p. 85: Systematophora cruta
Systematophora cruta is characterized by the possession of well-developed penitabular complexes and processes that are mostly solid, wide, cylindrical to tubiform, with simple or recurved distal extremities. The species differs from other species of Systematophora because of its short processes.
Strauss and Lund, 1988, p.173: This variety is an extreme representative of the very broad range of variational types accommodated by Systematophora placacantha. Consequently, all transitional types between S. placacantha s. s. and var. curta are known to occur.
The variety curta is always present in Northern German samples with rich and morphologically diverse populations of S. placacantha.