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Spiniferites membranaceus
Spiniferites membranaceus (Rossignol, 1964, p.86, pl.1, figs.4,9–10; pl.3, figs.7,12) Sarjeant, 1970, p.76.
Originally Hystrichosphaera furcata var. membranacea, subsequently Hystrichosphaera ramosa var. membranacea, thirdly Hystrichosphaera membranacea, fourthly (and now) Spiniferites membranaceus, fifthly Gonyaulax membranacea.
Because we follow the dual approach to the nomenclature of dinoflagellates (see Head et al. 2016), we retain this species in Spiniferites.
Motile equivalent: Gonyaulax spinifera (Claparède and Lachmann, 1859) Diesing, 1866, according to Dale (1976, table 2 — p.45) and Dodge (1989, p.289).
Holotype: Rossignol, 1964, pl.1, fig.4, 9-10
Locus typicus: Ashkelon, lsrael
Stratum typicum: Pleistocene-Recent
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Rossignol, 1964, p. 86, pl.1, fig.4,9-10, pl.3, fig.7,12
Hystrichosphaera furcata var. membranacea var. nov.
The folds of the outer test wall, which delimit the plates, rise and connect two neighbouring processes in a continuous curve at or below the level of trifurcation; where the processes are very close, the veils merge over the major part of their length. We see that this disposition is already present in the forms typical of this species, for the groups of two processes which separate two adjacent plates of the equatorial band. Here, the two large dorsal processes may be fused over their entire length up to the trifurcation, like the other four of the same plate are over a lesser extent: the external test layer is nearly completely detached from the internal layer.
Dimensions: test 57 x 50 µm, processes 20-25 µm.
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Supplemental description: Wall, 1967, p. 102-103: Hystrichosphaera membranacea
The test is circular, ovoid, or weakly-elongated (broader than high). Its surface is scabrate to microgranular and ornamented by membranous sutural septa which are stronger where they fuse at the corners of plate-areas. Distal projections arising from the septa are trifurcate or more complex at plate corners but bifurcate in between. There is a strong antapical dorsal and lateral range around plate-area 1"""" that is equal in height to one-third of the test diameter. The tabulation and plate pattern is typical for the genus. The archeopyle is dorsal and precingular (3"") and the furrow is weakly inclined and broader posteriorly. It is possible to recognize anterior, right accessory, right and left and posterior sulcal platelet-areas within the furrow; of these, the right sulcal is very small.
Affinities:
Wall, 1967, p.103: Hystrichosphaera membranacea
This uncommon species differs from Hystrichosphaera mirabilis by lacking strong rows of spines over its test; instead its processes are weak and membranous. It differs from H. scabrata by possessing a strong antapical flange. This appears to be a distinctive form which ranges back into the Miocene and worthy of elevation to specific status. Some small Tertiary specimens resemble H. bulloidea but lack two dorsal antapical spines seen in that species.
Originally Hystrichosphaera furcata var. membranacea, subsequently Hystrichosphaera ramosa var. membranacea, thirdly Hystrichosphaera membranacea, fourthly (and now) Spiniferites membranaceus, fifthly Gonyaulax membranacea.
Because we follow the dual approach to the nomenclature of dinoflagellates (see Head et al. 2016), we retain this species in Spiniferites.
Motile equivalent: Gonyaulax spinifera (Claparède and Lachmann, 1859) Diesing, 1866, according to Dale (1976, table 2 — p.45) and Dodge (1989, p.289).
Holotype: Rossignol, 1964, pl.1, fig.4, 9-10
Locus typicus: Ashkelon, lsrael
Stratum typicum: Pleistocene-Recent
-------------------------------------------------
Rossignol, 1964, p. 86, pl.1, fig.4,9-10, pl.3, fig.7,12
Hystrichosphaera furcata var. membranacea var. nov.
The folds of the outer test wall, which delimit the plates, rise and connect two neighbouring processes in a continuous curve at or below the level of trifurcation; where the processes are very close, the veils merge over the major part of their length. We see that this disposition is already present in the forms typical of this species, for the groups of two processes which separate two adjacent plates of the equatorial band. Here, the two large dorsal processes may be fused over their entire length up to the trifurcation, like the other four of the same plate are over a lesser extent: the external test layer is nearly completely detached from the internal layer.
Dimensions: test 57 x 50 µm, processes 20-25 µm.
----------------------------------------------------------
Supplemental description: Wall, 1967, p. 102-103: Hystrichosphaera membranacea
The test is circular, ovoid, or weakly-elongated (broader than high). Its surface is scabrate to microgranular and ornamented by membranous sutural septa which are stronger where they fuse at the corners of plate-areas. Distal projections arising from the septa are trifurcate or more complex at plate corners but bifurcate in between. There is a strong antapical dorsal and lateral range around plate-area 1"""" that is equal in height to one-third of the test diameter. The tabulation and plate pattern is typical for the genus. The archeopyle is dorsal and precingular (3"") and the furrow is weakly inclined and broader posteriorly. It is possible to recognize anterior, right accessory, right and left and posterior sulcal platelet-areas within the furrow; of these, the right sulcal is very small.
Affinities:
Wall, 1967, p.103: Hystrichosphaera membranacea
This uncommon species differs from Hystrichosphaera mirabilis by lacking strong rows of spines over its test; instead its processes are weak and membranous. It differs from H. scabrata by possessing a strong antapical flange. This appears to be a distinctive form which ranges back into the Miocene and worthy of elevation to specific status. Some small Tertiary specimens resemble H. bulloidea but lack two dorsal antapical spines seen in that species.