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Diconodinium longicorne
From Fensome et al., 2019:
Diconodinium longicorne Olaru, 1978a, p.89, pl.12, fig.6. Holotype: Olaru, 1978a, pl.12, fig.6; Olaru, 1978b, pl.1, fig.2 (not 3).
Olaru (1978b, p.38) also cited this species as new. Age: Campanian.
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Original description: [Olaru, 1978b] (translated from Romanian):
Diconodinium longicornis n. sp.
(Pl. I, fig. 3)
Holotypus: Preparation I/A, film 8/12, pl. I, fig. 3.
Derivatio nominis: The name comes from the rather long apical and antapical horns for the representatives of the genus Diconocinium.
Stratum typicum: Strata with inocerans, marly-calcareous intercalations in their middle part of Campanian age.
Locus typicus: Piriul Stejaru, left tributary of the Bistrița River.
Diagnosis: Subspherical rhomboidal capsule with equatorial cingulum. A characteristic tabulation is observed on the epitheca and hypotheca. It presents a thin, long apical horn and an asymmetrical antapical horn, thinner and shorter than the first.
Dimensions: Capsule, 65 x 60 μ; horn 32.30 μ; antapical horn 27.50 μ; total length of the form, 122.50 μ.
Description: The capsule is divided into two unequal parts by the equatorial cingulate cord. In the upper part, the tabulated epitheca that is prolonged
with the apical horn, is larger. In the lower part, the hypotheca with less visible tabulation, with an asymmetrical antapical horn, is smaller. The covering membrane is finely granulated, thin, without fringes.
Relationships and differences: It is morphologically similar to Diconodinium glabrum Eisenack & Cookson 1960 (1964, Eis. Katalog, Bd. I, L, 245). The described form, however, has a well-contoured capsule from which the two horns, apical and antapical, are detached. In the loose form, the cingulum is continuous, and the tabulation is observed on the surface of the capsule. The apical and antapical horns of the described form are much longer than those of Diconodinium glabrum.
Conclusions
A first conclusion that can be drawn from the analysis of these new forms, determined in the inoceramic layers, is that they lived and were sedimented in a warm, tropical or subtropical period of time, a climate otherwise characteristic of the Senonian.
A second conclusion that emerges from the material presented above concerns aspects of paleofloristic dynamics. The genus Aquilapollanites is not normally characteristic of this region. For the end of the Cretaceous, in the Central-European and Eastern European region another flora dominated, the Normapolles type, originating from the Central-European, North-Atlantic region. The Projectoaperturites group with the genus Aquilapollenites is characteristic of the Pacific-Siberian flora, which was widespread at that time in Siberia, the Far East, Canada and the northern U.S.A. The presence of the genus Aquilapollenites in the Carpathians indicates a floristic migration from the Pacific-Siberian area to the Central-European one. The generic Aquilapollenites was also cited in the Senonian deposits of the Modovenesca Plateau (Balteş, 1973), which confirms the idea mentioned above. The floristic migration was also observed in other plant groups, both for the territory of our country (Olaru, 1974) and for Central Europe (Krutzsch, 1966). Finally, the presence of a new genus, the genus Deflagimnium, which combines the characters of two initial genera, indicates that during this interval important changes occurred in the microflora, which prepared the foundation for a new flora, the Paleogene flora.
Diconodinium longicorne Olaru, 1978a, p.89, pl.12, fig.6. Holotype: Olaru, 1978a, pl.12, fig.6; Olaru, 1978b, pl.1, fig.2 (not 3).
Olaru (1978b, p.38) also cited this species as new. Age: Campanian.
---------------------------------------------------------------------------------------------------
Original description: [Olaru, 1978b] (translated from Romanian):
Diconodinium longicornis n. sp.
(Pl. I, fig. 3)
Holotypus: Preparation I/A, film 8/12, pl. I, fig. 3.
Derivatio nominis: The name comes from the rather long apical and antapical horns for the representatives of the genus Diconocinium.
Stratum typicum: Strata with inocerans, marly-calcareous intercalations in their middle part of Campanian age.
Locus typicus: Piriul Stejaru, left tributary of the Bistrița River.
Diagnosis: Subspherical rhomboidal capsule with equatorial cingulum. A characteristic tabulation is observed on the epitheca and hypotheca. It presents a thin, long apical horn and an asymmetrical antapical horn, thinner and shorter than the first.
Dimensions: Capsule, 65 x 60 μ; horn 32.30 μ; antapical horn 27.50 μ; total length of the form, 122.50 μ.
Description: The capsule is divided into two unequal parts by the equatorial cingulate cord. In the upper part, the tabulated epitheca that is prolonged
with the apical horn, is larger. In the lower part, the hypotheca with less visible tabulation, with an asymmetrical antapical horn, is smaller. The covering membrane is finely granulated, thin, without fringes.
Relationships and differences: It is morphologically similar to Diconodinium glabrum Eisenack & Cookson 1960 (1964, Eis. Katalog, Bd. I, L, 245). The described form, however, has a well-contoured capsule from which the two horns, apical and antapical, are detached. In the loose form, the cingulum is continuous, and the tabulation is observed on the surface of the capsule. The apical and antapical horns of the described form are much longer than those of Diconodinium glabrum.
Conclusions
A first conclusion that can be drawn from the analysis of these new forms, determined in the inoceramic layers, is that they lived and were sedimented in a warm, tropical or subtropical period of time, a climate otherwise characteristic of the Senonian.
A second conclusion that emerges from the material presented above concerns aspects of paleofloristic dynamics. The genus Aquilapollanites is not normally characteristic of this region. For the end of the Cretaceous, in the Central-European and Eastern European region another flora dominated, the Normapolles type, originating from the Central-European, North-Atlantic region. The Projectoaperturites group with the genus Aquilapollenites is characteristic of the Pacific-Siberian flora, which was widespread at that time in Siberia, the Far East, Canada and the northern U.S.A. The presence of the genus Aquilapollenites in the Carpathians indicates a floristic migration from the Pacific-Siberian area to the Central-European one. The generic Aquilapollenites was also cited in the Senonian deposits of the Modovenesca Plateau (Balteş, 1973), which confirms the idea mentioned above. The floristic migration was also observed in other plant groups, both for the territory of our country (Olaru, 1974) and for Central Europe (Krutzsch, 1966). Finally, the presence of a new genus, the genus Deflagimnium, which combines the characters of two initial genera, indicates that during this interval important changes occurred in the microflora, which prepared the foundation for a new flora, the Paleogene flora.