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Deflandrea heterophlycta

Deflandrea heterophlycta Deflandre and Cookson, 1955

Tax. sr. synonym of Deflandrea endopapillata Archangelsky, 1969, according to Stover and Evitt, 1978.
Deflandrea heterophlycta was a nomen nudum in Deflandre and Cookson, 1954.
Holotype: Deflandre and Cookson, 1955, text-fig.5; Verdier, 1970, pl.1, figs.1-4
Locus typicus: Castle Cove, Victoria, Australia
Stratum typicum: Late Eocene
Translation Gocht, 1969: Geological Survey of Canada

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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.

Deflandrea heterophlycta Deflandre and Cookson, 1955, has a rounded endocyst with tubercles more numerous and coarser towards the poles. The tubercles at the poles may as large as 13 by 5 µm. But like the smaller tubercles, they are always solid and have a granular surface. Cyst membrane finely punctate. Membrane of pericyst finely and sparsely punctate. Size: length 115 µm, width 80 µm, endocyst 70 by 72 µm.
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Original description: Deflandre and Cookson, 1955, p.249-250
Epitheca broadly conical with slightly convex flanks and a somewhat rounded, unthickened apex; hypotheca a little smaller than the epitheca and provided with 2 short, blunt, slightly divergent horns. Transverse girdle clear but shallow. Cyst sphaeroidal, ornamented with irregularly dispersed tubercles more numerous and coeser towards the poles. Cyst membrane finely punctate. Operning laterally extended situated towards the apical pole. Membrane of theca very finely and sparsely punctate.
Dimensions: Total length 115 µm, breadth 80 µm; cyst 72x72 µm.

Affinities:
Deflandre and Cookson, 1955, p.250: The general form of this species recalls D. phosphoritica but it is clearly distinct in the tuberculate ornamentation of the cyst.

Gocht, 1969, p. 11-12:
Deflandrea cf. heterophlycta Deflandre and Cookson, 1955
The three specimens came from sample 19 (Middle Oligocene) and were all badly damaged.
Its affinity with the Australian species can be inferred from the inner body, which has distinct projections on the surface; however, they are not as long as on the specimens of Deflandre and Cookson, 1955.
Also the outer armor bears numerous very small projections, which mark certain distinctly bounded fields and leave others free or nearly free. Likewise the cingulum is marked by small processes. Unfortunately, the tabulation expressed by these fields could not be determined.
Deflandre and Cookson, 1955 mention a "very fine and sparse" punctation of the theca in D. heterophlycta. Evidently, in that case no distinct areation emerges. Alberti, 1959 describes a Deflandrea cf. heterophlycta which also has finely punctate armor; but it has a very different habit, and its inner body is relatively small. The finds of Deflandre and Cookson and of Alberti all date from the Eocene, as do those of Cookson and Eisenack, 1965 (Deflandrea heterophlycta; Plate 11, fig.10; D. cf. heterophlycta, with smooth outer membrane).
A D. heterophlycta var. pusulosa described by Rozen, 1965 is evidently related to D. phosphoritica. None of the forms mentioned can be identified with our specimens.
Occurrence: Middle Oligocene.

Heilmann-Clausen in Heilmann-Clausen and Costa, 1989, p.464, pl.7, figs.3,4: Deflandrea cf. heterophlycta
Rozen, 1965: Deflandrea heterophlycta forma pusulosa
De Conick, 1985: Deflandrea leptodermata
The tubercles on the endophragm are lower and less numerous, than typical for D. heterophlycta. Forma pusulosa is considered as a jr. syn. of Deflandrea phosphoritica by Lentin and Williams, 1976. The present author agrees that the difference in morphology is very minor. For stratigraphical purposes, however, it appears useful to discriminate the present forms.
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