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Operculodinium kebumenum
From Fensome et al., 2019:
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Original description Morgenroth et al., 2008:
Derivation of name: The species is named after the town Kebumen, located close to the Kali Jaya outcrops.
Holotype: Pl. 1, Figs 12, 13. Sample KJ-9, single grain slide KJ-9/30.
Paratypes: Single grain slide KJ-6/50, sample KJ-6, single grain slides KJ-9/8 and KJ-9/12, sample KJ-9, single grain slide KJ-7/2, sample KJ-7.
Type locality: Kali Jaya, Central Java (text-figure 4). ?Upper Early -Lower Middle Miocene, Age N ?6, N 8 -N 10.
Diagnosis: Large, ovoidal to spherical, proximate cysts with a reticulate wall and short appendages (virgae). The virgae are usually conical, rarely subconical and appear to be massive. Their base may be reticulated while their distal part is smooth. the density of virgae varies strongly on different specimens. On some specimens, virae mabe oriented indicating a gonyaulacalean field pattern. Archeopyle precingular, simple.
Description: The large cysts are usually ovoidal, rarely spherical with a reticulated wall, which is 1一2 µm thick. From the cyst short appendages (virgae) arise, which are mostly conical, rarely subconical. The reticulation of the wall often extends into the basal part of the virgae, while their distal part is smooth or faintly striated. The number of virgae may vary strongly between specimens, while their length is rather constant between 3 and 5 µm. Some specimens have only indications of rudimentary virgae. Usually the virgae do not indicate any field Panern, however, specimens occur, on which the virgae are arranged, indicating a gonyaulacalean field pattern. The archeopyle is simple, precingular Type P, detached and reflecting the position of 3".
Dimensions: Length excluding virgae, 68 (77) 98 µm, holotype 77 µm, width excluding appendages/ virgae, 53 (67) 86 µm, holotype 74 µm. Virgae 2-6 µm. 30 specimens measured.
Comparison: Operculodinium kebumenum sp. nov. differs from Opergulodinium giganteum Wall 1967 from the Pleistocene of the Yukatan Basin, in the type of appendages which in O. giganteum are tiny and capitate (WALL 1967: 112). Operculodinium as floridium WARNY and WRENN 1997 from the Miocene of Morocco has fibrous, intratabular spines, separated by unornamented parasututural bands (WARNY & WRENN 1997: 287, 290, pl. Ii°I, figs 2, 3, 6, pl. IV, fig. 5), while the new species has different appendages, which are only occasionally arranged to reflect a gonyaulacalean field pattern and which, in those specimens, seem to partly delineate sutures.
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Original description Morgenroth et al., 2008:
Derivation of name: The species is named after the town Kebumen, located close to the Kali Jaya outcrops.
Holotype: Pl. 1, Figs 12, 13. Sample KJ-9, single grain slide KJ-9/30.
Paratypes: Single grain slide KJ-6/50, sample KJ-6, single grain slides KJ-9/8 and KJ-9/12, sample KJ-9, single grain slide KJ-7/2, sample KJ-7.
Type locality: Kali Jaya, Central Java (text-figure 4). ?Upper Early -Lower Middle Miocene, Age N ?6, N 8 -N 10.
Diagnosis: Large, ovoidal to spherical, proximate cysts with a reticulate wall and short appendages (virgae). The virgae are usually conical, rarely subconical and appear to be massive. Their base may be reticulated while their distal part is smooth. the density of virgae varies strongly on different specimens. On some specimens, virae mabe oriented indicating a gonyaulacalean field pattern. Archeopyle precingular, simple.
Description: The large cysts are usually ovoidal, rarely spherical with a reticulated wall, which is 1一2 µm thick. From the cyst short appendages (virgae) arise, which are mostly conical, rarely subconical. The reticulation of the wall often extends into the basal part of the virgae, while their distal part is smooth or faintly striated. The number of virgae may vary strongly between specimens, while their length is rather constant between 3 and 5 µm. Some specimens have only indications of rudimentary virgae. Usually the virgae do not indicate any field Panern, however, specimens occur, on which the virgae are arranged, indicating a gonyaulacalean field pattern. The archeopyle is simple, precingular Type P, detached and reflecting the position of 3".
Dimensions: Length excluding virgae, 68 (77) 98 µm, holotype 77 µm, width excluding appendages/ virgae, 53 (67) 86 µm, holotype 74 µm. Virgae 2-6 µm. 30 specimens measured.
Comparison: Operculodinium kebumenum sp. nov. differs from Opergulodinium giganteum Wall 1967 from the Pleistocene of the Yukatan Basin, in the type of appendages which in O. giganteum are tiny and capitate (WALL 1967: 112). Operculodinium as floridium WARNY and WRENN 1997 from the Miocene of Morocco has fibrous, intratabular spines, separated by unornamented parasututural bands (WARNY & WRENN 1997: 287, 290, pl. Ii°I, figs 2, 3, 6, pl. IV, fig. 5), while the new species has different appendages, which are only occasionally arranged to reflect a gonyaulacalean field pattern and which, in those specimens, seem to partly delineate sutures.