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Impagidinium minus
Impagidinium minor Biffi and Manum, 1988
Holotype: Biffi and Manum 1988, pl. 12, figs. 9-11
Locus typicus: Monte Conero Section; Scaglia Cinerea Formation.
Stratum typicum: Early Miocene
Age: Late Oligocene-Early Miocene
Diagnosis: Biffi and manum 1988, p. 206, 207
Subsphaerical species of Impagidinium, characterized by foldlike sutural crests of the periphragm, showing the same punctate structure as the periphragm in the intratabular areas, and by the small size (about 35Ám). Paraplate 6" has no contact with the apical series.
Dimensions -- Holotype: cyst length 40 µm; breadth 34 µm. Mean values (bracketed) and extremes (n = 15): cyst length 28(36)42 µm; breadth 28(32)34 µm.
Description: Biffi and manum 1988, p. 206, 207
Proximate cysts of subsphaerical to ovoidal shape, epi and hypocyst of approximately equal size. Cyst wall 1.5- 2.0 µm thick, two-layered. Endophragm apparently unstructured, periphragm somewhat thicker and of spongy appearance, in surface view irregularly punctate. The two layers are closely appressed except along parasutures where narrow pericoels are formed by foldlike crests of the periphragm, 1.5-2.0 Ám high, rarely 2.5, showing the same punctate structure as periphragm in the intratabular areas. In surface view of the cyst wall, crest bases appear as pairs of rugged parallel lines approximately 0.5Ám apart. Paratabulation 3", 6", 6c, 5"", lp, 1"", ps. The apical series has only one ventral paraplate, 6" is small and triangular in shape with no contact with paraplate 1", only with sulcus (Pl. 12, fig. 9). Archeopyle precingular, formed by loss of paraplate 3".
Remarks: Biffi and manum 1988, p. 206, 207
These very typical cysts belong to the Impagidinium/Leptodinium species with a spongy wall, which are rather frequent in our samples. Impagidinium minor n. sp. is very well characterized by its small size, the structure of the crests, and the 6" in contact with the as only
Occurrences:
Monte Conero SR 995 - SR 996common
Ca" Fusconi PAL 92 - PAL 102rare to common
Montebello d"Urbino PAL 110 - PAL 123rare to common
Ca" TosiPAL 205 PAL 208 rare
Holotype: Biffi and Manum 1988, pl. 12, figs. 9-11
Locus typicus: Monte Conero Section; Scaglia Cinerea Formation.
Stratum typicum: Early Miocene
Age: Late Oligocene-Early Miocene
Diagnosis: Biffi and manum 1988, p. 206, 207
Subsphaerical species of Impagidinium, characterized by foldlike sutural crests of the periphragm, showing the same punctate structure as the periphragm in the intratabular areas, and by the small size (about 35Ám). Paraplate 6" has no contact with the apical series.
Dimensions -- Holotype: cyst length 40 µm; breadth 34 µm. Mean values (bracketed) and extremes (n = 15): cyst length 28(36)42 µm; breadth 28(32)34 µm.
Description: Biffi and manum 1988, p. 206, 207
Proximate cysts of subsphaerical to ovoidal shape, epi and hypocyst of approximately equal size. Cyst wall 1.5- 2.0 µm thick, two-layered. Endophragm apparently unstructured, periphragm somewhat thicker and of spongy appearance, in surface view irregularly punctate. The two layers are closely appressed except along parasutures where narrow pericoels are formed by foldlike crests of the periphragm, 1.5-2.0 Ám high, rarely 2.5, showing the same punctate structure as periphragm in the intratabular areas. In surface view of the cyst wall, crest bases appear as pairs of rugged parallel lines approximately 0.5Ám apart. Paratabulation 3", 6", 6c, 5"", lp, 1"", ps. The apical series has only one ventral paraplate, 6" is small and triangular in shape with no contact with paraplate 1", only with sulcus (Pl. 12, fig. 9). Archeopyle precingular, formed by loss of paraplate 3".
Remarks: Biffi and manum 1988, p. 206, 207
These very typical cysts belong to the Impagidinium/Leptodinium species with a spongy wall, which are rather frequent in our samples. Impagidinium minor n. sp. is very well characterized by its small size, the structure of the crests, and the 6" in contact with the as only
Occurrences:
Monte Conero SR 995 - SR 996common
Ca" Fusconi PAL 92 - PAL 102rare to common
Montebello d"Urbino PAL 110 - PAL 123rare to common
Ca" TosiPAL 205 PAL 208 rare