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Hystrichosphaera scabrata
Hystrichosphaera scabrata Wall, 1967, p.102
Now Spiniferites. Originally Hystrichosphaera, subsequently (and now) Spiniferites. This is a cyst equivalent of Gonyaulax spinifera (Claparede and Lachmann, 1859) Diesing, 1866, according to Dodge, 1989.
Holotype: Wall, 1967, pl.14, figs.10-13
Locus typicus: Yucatan Basin
Stratum typicum: Pleistocene-Recent
Original diagnosis: Wall, 1967, p. 102
A species of Hystrichosphaera with microgranular sutural septa, membranous processes and a broad posterior ventral area.
Dimensions. Test 48-55 µm, processes 10-17 µm. Numerous examples.
Original description: Wall, 1967, p. 102
The theca is ovoid with broadly rounded apices and divided into epithecal and hypothecal hemispheres by a narrow descending girdle displaced by its own width ventrally. The test wall is thin, its outer layer forming microgranular sutural septa. Their outline in optical section is undulate and their height equivalent to one-third of the test diameter. These septa unite at the corners of plate-areas to form spine-like processes with trifurcate or further subdivided tips with strongly divergent angles. Its tabulation is typical for the genus, 3-4", 0a, 6"", 6g, 5-6""", 1p and 1"""", and the plate pattern as for H. furcata and H. bentori. A complex process occurs at the head of the longitudinal furrow, above which, the two ventral apical plate areas (1", 4") are situated; they may be incompletely separated. The furrow is weakly inclined and has at least four constituent platelet-areas. Usually, however, only the posterior sulcal platelet is obvious. In the postero-ventral area the posterior intercalary plate-area is well developed and almost as broad as the furrow itself at this point. The archeopyle is typical (3"") and weakly rounded.
Now Spiniferites. Originally Hystrichosphaera, subsequently (and now) Spiniferites. This is a cyst equivalent of Gonyaulax spinifera (Claparede and Lachmann, 1859) Diesing, 1866, according to Dodge, 1989.
Holotype: Wall, 1967, pl.14, figs.10-13
Locus typicus: Yucatan Basin
Stratum typicum: Pleistocene-Recent
Original diagnosis: Wall, 1967, p. 102
A species of Hystrichosphaera with microgranular sutural septa, membranous processes and a broad posterior ventral area.
Dimensions. Test 48-55 µm, processes 10-17 µm. Numerous examples.
Original description: Wall, 1967, p. 102
The theca is ovoid with broadly rounded apices and divided into epithecal and hypothecal hemispheres by a narrow descending girdle displaced by its own width ventrally. The test wall is thin, its outer layer forming microgranular sutural septa. Their outline in optical section is undulate and their height equivalent to one-third of the test diameter. These septa unite at the corners of plate-areas to form spine-like processes with trifurcate or further subdivided tips with strongly divergent angles. Its tabulation is typical for the genus, 3-4", 0a, 6"", 6g, 5-6""", 1p and 1"""", and the plate pattern as for H. furcata and H. bentori. A complex process occurs at the head of the longitudinal furrow, above which, the two ventral apical plate areas (1", 4") are situated; they may be incompletely separated. The furrow is weakly inclined and has at least four constituent platelet-areas. Usually, however, only the posterior sulcal platelet is obvious. In the postero-ventral area the posterior intercalary plate-area is well developed and almost as broad as the furrow itself at this point. The archeopyle is typical (3"") and weakly rounded.