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Hystrichosphaera membranacea
Hystrichosphaera membranacea (Rossignol, 1964) Wall, 1967
NOW Spiniferites membranaceus. Originally Hystrichosphaera furcata var. membranacea, subsequently Hystrichosphaera ramosa var. membranacea, thirdly Hystrichosphaera membranacea, fourthly (and now) Spiniferites membranaceus, fifthly Gonyaulax membranacea.
This is a cyst equivalent of Gonyaulax spinifera (Claparede and Lachmann, 1859) Diesing, 1866, according to Dodge, 1989.
Holotype: Rossignol, 1964, pl.1, figs.4,9-10
Locus typicus: Ashkelon, lsrael
Stratum typicum: Pleistocene-Recent
Original description: Rossignol, 1964, p. 86: Hystrichosphaera furcata var. membraneacea
Supplemental description: Wall, 1967, p. 102-103
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: 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.
NOW Spiniferites membranaceus. Originally Hystrichosphaera furcata var. membranacea, subsequently Hystrichosphaera ramosa var. membranacea, thirdly Hystrichosphaera membranacea, fourthly (and now) Spiniferites membranaceus, fifthly Gonyaulax membranacea.
This is a cyst equivalent of Gonyaulax spinifera (Claparede and Lachmann, 1859) Diesing, 1866, according to Dodge, 1989.
Holotype: Rossignol, 1964, pl.1, figs.4,9-10
Locus typicus: Ashkelon, lsrael
Stratum typicum: Pleistocene-Recent
Original description: Rossignol, 1964, p. 86: Hystrichosphaera furcata var. membraneacea
Supplemental description: Wall, 1967, p. 102-103
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: 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.