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Nematosphaeropsis lativittatus
Nematosphaeropsis lativittatus Wrenn, 1988
synonym: Nematosphaeropsis sp. A, Wrenn and Kokinos, 1986, p. 186, pl. 3, figs. 1-4, 6, pl. 17, fig 4.
Holotype. Wrenn 1988: Plate 1, figs. 12-15, 18
Locus typicus: Eureka core E67-135, offshore deposits of the northeastern Gulf of Mexico.
Stratum typicum: Pliocene
Age: Pliocene
Diagnosis: Wrenn, 1988, p. 140, 142: Nematosphaeropsis lativittatus
A species of Nematosphaeropsis characterized by hollow, triangular, trifurcate gonal and (?)intergonal processes that expand markedly at their distal end and give rise to very broad, flat penitabular trabeculae. Two wide penitabular trabeculae arise from each furcation. Each trabeculum of a pair joining adjacent processes arises from a different terminal furcation of the joined processes. The trabeculae may be joined to each other by strands or direct fusing in the span between the processes that they are connecting.
Description: Wrenn, 1988, p. 140, 142: Nematosphaeropsis lativittatus
Shape: Subspherical central body surrounded by a concentric network of paired, broad, ribbon-like penitabular trabeculae supported by hollow, distally open processes. The processes are triangular in cross-section. The dense network of processes and trabeculae obscures the central body and the distribution of processes on most specimens.
Phragma: The smooth, thin (<0.5 Ám) wall of the central body gives rise to microgranular, hollow infundibular gonal and (?)intergonal processes that do not communicate with the endocoel. A stout rib extends along each corner of the hollow, triangular process shafts. Each process shaft flares markedly just short of its distal end, and appears Y-shaped or almost T-shaped in optical section. The trifurcate process termination splay out into flat, broad penitabular trabeculae, two of which connect each process furcation to the furcations of neighboring processes.
Paratabulation: Paraplate areas may be outlined by the trabeculae, though they are generally diff1cult to observe because the densely distributed, flexible processes, and because trabeculae tend to collapse onto the thin, flexible wall of the central body. However, the paratabulation formula occasionally displayed on the trabecular shell appears to be ?3-4", 5-6", 6c, 5-6"", ?p, 1"".
Paracingulum: Six transversely elongate paracingular paraplate areas can be outlined by trabeculae. Parasulcus: An elongate, undivided parasulcal area may be outline by trabeculae on some specimens, though this is usually evident only on a scanning electron microscope (SEM).
Archeopyle: Precingular (?).
Dimensions: Overall diameter 39-54 Ám (mean 45 Ám); central body diameter 17-31 Ám (mean 24 Ám); process length 8-12 Ám. Ten specimens measured.
Comparison. Wrenn, 1988, p. 140, 142
Nematosphaeropsis lativittatus sp. nov. differs from all other species of Nematosphaeropsis recognized in this paper in that it is smaller, generally compact, and has Y- or T-shaped infundibular processes that are connected distally by very broad, often fused, ribbon-like trabeculae. This species can be superifically similar to Unipontidinium aquaeductum gen. et comb. nov., however, N. Iativittatus sp. nov. exhibits pairs of penitabular trabeculae rather than single parasutural trabeculae. In addition, the processes and trabeculae on N. lativittatus sp. nov. are more numerous and very much broader.
synonym: Nematosphaeropsis sp. A, Wrenn and Kokinos, 1986, p. 186, pl. 3, figs. 1-4, 6, pl. 17, fig 4.
Holotype. Wrenn 1988: Plate 1, figs. 12-15, 18
Locus typicus: Eureka core E67-135, offshore deposits of the northeastern Gulf of Mexico.
Stratum typicum: Pliocene
Age: Pliocene
Diagnosis: Wrenn, 1988, p. 140, 142: Nematosphaeropsis lativittatus
A species of Nematosphaeropsis characterized by hollow, triangular, trifurcate gonal and (?)intergonal processes that expand markedly at their distal end and give rise to very broad, flat penitabular trabeculae. Two wide penitabular trabeculae arise from each furcation. Each trabeculum of a pair joining adjacent processes arises from a different terminal furcation of the joined processes. The trabeculae may be joined to each other by strands or direct fusing in the span between the processes that they are connecting.
Description: Wrenn, 1988, p. 140, 142: Nematosphaeropsis lativittatus
Shape: Subspherical central body surrounded by a concentric network of paired, broad, ribbon-like penitabular trabeculae supported by hollow, distally open processes. The processes are triangular in cross-section. The dense network of processes and trabeculae obscures the central body and the distribution of processes on most specimens.
Phragma: The smooth, thin (<0.5 Ám) wall of the central body gives rise to microgranular, hollow infundibular gonal and (?)intergonal processes that do not communicate with the endocoel. A stout rib extends along each corner of the hollow, triangular process shafts. Each process shaft flares markedly just short of its distal end, and appears Y-shaped or almost T-shaped in optical section. The trifurcate process termination splay out into flat, broad penitabular trabeculae, two of which connect each process furcation to the furcations of neighboring processes.
Paratabulation: Paraplate areas may be outlined by the trabeculae, though they are generally diff1cult to observe because the densely distributed, flexible processes, and because trabeculae tend to collapse onto the thin, flexible wall of the central body. However, the paratabulation formula occasionally displayed on the trabecular shell appears to be ?3-4", 5-6", 6c, 5-6"", ?p, 1"".
Paracingulum: Six transversely elongate paracingular paraplate areas can be outlined by trabeculae. Parasulcus: An elongate, undivided parasulcal area may be outline by trabeculae on some specimens, though this is usually evident only on a scanning electron microscope (SEM).
Archeopyle: Precingular (?).
Dimensions: Overall diameter 39-54 Ám (mean 45 Ám); central body diameter 17-31 Ám (mean 24 Ám); process length 8-12 Ám. Ten specimens measured.
Comparison. Wrenn, 1988, p. 140, 142
Nematosphaeropsis lativittatus sp. nov. differs from all other species of Nematosphaeropsis recognized in this paper in that it is smaller, generally compact, and has Y- or T-shaped infundibular processes that are connected distally by very broad, often fused, ribbon-like trabeculae. This species can be superifically similar to Unipontidinium aquaeductum gen. et comb. nov., however, N. Iativittatus sp. nov. exhibits pairs of penitabular trabeculae rather than single parasutural trabeculae. In addition, the processes and trabeculae on N. lativittatus sp. nov. are more numerous and very much broader.