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Achomosphaera jayana
From Fensome et al., 2019:
Achomosphaera jayana Morgenroth et al., 2008, p.123, pl.5, figs.10–13; pl.6, figs.1–4.
Holotype: Morgenroth et al., 2008, pl.5, fig.10.
Age: late Early to early Middle Miocene.
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Original description Morgenroth et al., 2008:
Derivation of name: The species is named after the Kali Jaya River, Central Java, where it occurs in the section studied.
Holotype: Pl. 5, Fig. 10. Sample KJ-27, single grain slide KJ-27/51.
Paratypes: Single grain slides KH9/2, KJ-19/3 from sample KJ-19, and KJ-27/50, KJ-27/60 from sample KJ-27.
Type locality: Kali Jaya, Central Java (Text-fig. 4). ?Upper Early - Lower Middle Miocene, Age N?6; N8- N11.
Diagnosis: An intermediate species of Achomosphaera with the following characteristics: cyst ovoidal to subspherical; the periphragm is strongly granulated; processes seem to be gonal, their sturdy(?massive) stems are smooth to faintly striate and their shape variable: foliate, digitate or distally branched. Some specimens show faint indications of paratabulation.
Description: The medium sized cysts are ovoidal to subspherical and have a clearly granulated periphragm. A field pattern is absent on most specimens, however: a few have faint indications of ridges, which seem to reflect a gonyaulacalean field pattern. The sturdy processes seem to be gonal. Their bases can be triangular or elongated and their stems are normally smooth;· but sometimes show faint striations, their distal shape varies considerable and buccinate, foliate, digitate and branched processes have been observed. Specimens show a simple precingular archeopyle (?3").
Dimensions: Length excluding processes, 37 (47) 55 μm, holotype 37 μm, width excluding processes, 32 (38) 47 μm, holotype 40 μm. Processes 12-15 μm, rarely 17 μm. 50 specimens measured.
Comparisons : The new species can be distinguished from the species previously described under Achomosphaera mainly by its sturdy processes, which are foliate, digitate or distally branched.
Achomosphaera jayana Morgenroth et al., 2008, p.123, pl.5, figs.10–13; pl.6, figs.1–4.
Holotype: Morgenroth et al., 2008, pl.5, fig.10.
Age: late Early to early Middle Miocene.
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Original description Morgenroth et al., 2008:
Derivation of name: The species is named after the Kali Jaya River, Central Java, where it occurs in the section studied.
Holotype: Pl. 5, Fig. 10. Sample KJ-27, single grain slide KJ-27/51.
Paratypes: Single grain slides KH9/2, KJ-19/3 from sample KJ-19, and KJ-27/50, KJ-27/60 from sample KJ-27.
Type locality: Kali Jaya, Central Java (Text-fig. 4). ?Upper Early - Lower Middle Miocene, Age N?6; N8- N11.
Diagnosis: An intermediate species of Achomosphaera with the following characteristics: cyst ovoidal to subspherical; the periphragm is strongly granulated; processes seem to be gonal, their sturdy(?massive) stems are smooth to faintly striate and their shape variable: foliate, digitate or distally branched. Some specimens show faint indications of paratabulation.
Description: The medium sized cysts are ovoidal to subspherical and have a clearly granulated periphragm. A field pattern is absent on most specimens, however: a few have faint indications of ridges, which seem to reflect a gonyaulacalean field pattern. The sturdy processes seem to be gonal. Their bases can be triangular or elongated and their stems are normally smooth;· but sometimes show faint striations, their distal shape varies considerable and buccinate, foliate, digitate and branched processes have been observed. Specimens show a simple precingular archeopyle (?3").
Dimensions: Length excluding processes, 37 (47) 55 μm, holotype 37 μm, width excluding processes, 32 (38) 47 μm, holotype 40 μm. Processes 12-15 μm, rarely 17 μm. 50 specimens measured.
Comparisons : The new species can be distinguished from the species previously described under Achomosphaera mainly by its sturdy processes, which are foliate, digitate or distally branched.