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Nannoceratopsis plegas ssp. plegas
From Fensome et al., 2019:
Nannoceratopsis plegas ssp. plegas Autonym. Emendation: Prauss, 1989, p.15, as Nannoceratopsis plegas var. plegas.
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Holotype: Drugg, 1978, pl.6, fig.8. NIA
Paratypes: Drugg, 1978, pl. 6, fig. 9
Stratum typicum: Aalenian
Locus typicus: Eschach, Swabia, Germany
Original description: Drugg, 1978, p. 71
Diagnosis: Cyst outline more or less sickle-shaped. The dorsal horn is elongate and the ventral horn is comparatively short. The antapical cavity is broad and flattened to arcuate. The periphragm usually extends beyond the endophragm at the tips of the antapical horns to form short sack-like extensions. The wall is finely pitted or areolate but this appearance may represent a preservational feature. Low inconspicuous ridges border the lateral edges. The total cyst length ranges from 73 to 109 µm. Measurements based on 23 specimens.
Affinities:
Drugg, 1978, p. 71: The elongated dorsal horn with its consequent effect on the cyst outline distinguishes this species from all other described species of Nannoceratopsis. It is most closely allied to N. gracilis Alberti, 1961, although some variants share characteristics with N. pellucida Deflandre, 1938.
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Emended description: [Prauss, 1989] (translated from German):
Emended description: A variation of N. plegas with a strongly elongated dorsal and distinct ventral antapic horn. The large difference in length between the two horns is characteristic, giving the form the typical sickle-shaped habitus.
Remarks: The main morphological difference from N. plegas var. brevicornus is the large difference in length between the dorsal and ventral antapical horns. In addition, the antapical indentation between the horns is more rounded and concave and is often somewhat flatter.
Stratigraphically, in contrast to var. brevicornus, the form only appears quantitatively from the U'Aalenian onwards.
Occurrence: O'Toarcian to M'Bajocian, levesquei- to humphriesianum-Zone.
Nannoceratopsis plegas ssp. plegas Autonym. Emendation: Prauss, 1989, p.15, as Nannoceratopsis plegas var. plegas.
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Holotype: Drugg, 1978, pl.6, fig.8. NIA
Paratypes: Drugg, 1978, pl. 6, fig. 9
Stratum typicum: Aalenian
Locus typicus: Eschach, Swabia, Germany
Original description: Drugg, 1978, p. 71
Diagnosis: Cyst outline more or less sickle-shaped. The dorsal horn is elongate and the ventral horn is comparatively short. The antapical cavity is broad and flattened to arcuate. The periphragm usually extends beyond the endophragm at the tips of the antapical horns to form short sack-like extensions. The wall is finely pitted or areolate but this appearance may represent a preservational feature. Low inconspicuous ridges border the lateral edges. The total cyst length ranges from 73 to 109 µm. Measurements based on 23 specimens.
Affinities:
Drugg, 1978, p. 71: The elongated dorsal horn with its consequent effect on the cyst outline distinguishes this species from all other described species of Nannoceratopsis. It is most closely allied to N. gracilis Alberti, 1961, although some variants share characteristics with N. pellucida Deflandre, 1938.
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Emended description: [Prauss, 1989] (translated from German):
Emended description: A variation of N. plegas with a strongly elongated dorsal and distinct ventral antapic horn. The large difference in length between the two horns is characteristic, giving the form the typical sickle-shaped habitus.
Remarks: The main morphological difference from N. plegas var. brevicornus is the large difference in length between the dorsal and ventral antapical horns. In addition, the antapical indentation between the horns is more rounded and concave and is often somewhat flatter.
Stratigraphically, in contrast to var. brevicornus, the form only appears quantitatively from the U'Aalenian onwards.
Occurrence: O'Toarcian to M'Bajocian, levesquei- to humphriesianum-Zone.