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Achomosphaera clavata
From Fensome et al., 2019:
Achomosphaera clavata, Morgenroth et al., 2008, p.122–123, pl.5, figs.6–9.
Holotype: Morgenroth et al., 2008, pl.5, figs.6–7.
Age: Late Miocene.
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Original description: [Morgenroth et al., 2008, p. 122-123]:
Achomosphaera clavata sp. nov.
Plate 5, Figs 6-9
Derivation of name: Latin, clavus, steering, with reference to the lateral membranous flange.
Holotype: plate 5, Figs 6, 7. Single grain slide CP-25/68, sample CP-25.
Paratype: single grain slide CP-26/20, sample CP-26.
Type locality: Cipamingkis River, West Java (Text-fig. 5). Cisubuh Formation, Late Miocene, Age N 17.
Diagnosis: a large to intermediate species of Achomosphaera with an ovoidal to subspherical cyst; wall smooth to finely granular; processes with smooth shafts, trifurcate or bifid at their distal ends, often with bifid tips. On the right side of the cyst a high membranous flange is present. It is located at ca. 90 from the archeopyle and about at the level fo the cingulum.
Description: The large to intermediate cyst is ovoidal to subspherical, tabulation is weakly defined by few low and discontinuous ridges; the cyst wall is made up of both, periphragm and endophragm, the periphragm being smooth to finely granular; processes with smooth shafts appear to be gonal; they are trifurcate or bifid, the distal ends of the furcations are often surmounted by bifid tips. The archeopyle is simple, precingular (3''). On the right side of the cyst, at some 90° from the archeopyle and about at the level of the cingulum, a characteristic membranous flange, some 25 µm high, is present. The membrane of the flange is finely granular to smooth and distally capped by bifid or trifurcate extensions, as present on the processes.
Dimensions: Length excluding processes, 49 (54) 58 µm, holotype 58 µm, width excluding processes, 35 (43) 50 µm, holotype 50 µm. Processes 15-20 µm. 11 specimens measured.
Comparisons – Cysts with membranous flanges on the hyposome or at the antapex have been described, viz. Hystrichostrogylon Agelopoulos and Spiniferites mirabilis (Rossignol). This new species differs from such species by having one membranous flange, which is located at the cingular area of the cyst, to the right of the archeopyle.
Achomosphaera clavata, Morgenroth et al., 2008, p.122–123, pl.5, figs.6–9.
Holotype: Morgenroth et al., 2008, pl.5, figs.6–7.
Age: Late Miocene.
---------------------------------------------------------------------------------------------------
Original description: [Morgenroth et al., 2008, p. 122-123]:
Achomosphaera clavata sp. nov.
Plate 5, Figs 6-9
Derivation of name: Latin, clavus, steering, with reference to the lateral membranous flange.
Holotype: plate 5, Figs 6, 7. Single grain slide CP-25/68, sample CP-25.
Paratype: single grain slide CP-26/20, sample CP-26.
Type locality: Cipamingkis River, West Java (Text-fig. 5). Cisubuh Formation, Late Miocene, Age N 17.
Diagnosis: a large to intermediate species of Achomosphaera with an ovoidal to subspherical cyst; wall smooth to finely granular; processes with smooth shafts, trifurcate or bifid at their distal ends, often with bifid tips. On the right side of the cyst a high membranous flange is present. It is located at ca. 90 from the archeopyle and about at the level fo the cingulum.
Description: The large to intermediate cyst is ovoidal to subspherical, tabulation is weakly defined by few low and discontinuous ridges; the cyst wall is made up of both, periphragm and endophragm, the periphragm being smooth to finely granular; processes with smooth shafts appear to be gonal; they are trifurcate or bifid, the distal ends of the furcations are often surmounted by bifid tips. The archeopyle is simple, precingular (3''). On the right side of the cyst, at some 90° from the archeopyle and about at the level of the cingulum, a characteristic membranous flange, some 25 µm high, is present. The membrane of the flange is finely granular to smooth and distally capped by bifid or trifurcate extensions, as present on the processes.
Dimensions: Length excluding processes, 49 (54) 58 µm, holotype 58 µm, width excluding processes, 35 (43) 50 µm, holotype 50 µm. Processes 15-20 µm. 11 specimens measured.
Comparisons – Cysts with membranous flanges on the hyposome or at the antapex have been described, viz. Hystrichostrogylon Agelopoulos and Spiniferites mirabilis (Rossignol). This new species differs from such species by having one membranous flange, which is located at the cingular area of the cyst, to the right of the archeopyle.