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Cousteaudinium aubryae subsp. gonoperforatum

Cousteaudinium aubryae subsp. gonoperforatum Strauss in Strauss et al., 2001, p. 403-404, pl.1, figs.1-3.
Originally Thalassiphora gonoperforata (name not validly published), subsequently (and now) Cousteaudinium aubryae subsp. gonoperforatum.
Holotype: Strauss et al., pl.1, fig.2.
Age: Mid Miocene.

Original description (Strauss et. al, 2001)
Derivation of name: to emphasize the tectum perforation in the gonal position.
Holotype: sample 9/128.50 m, Pl. 1, fig. 2
Paratype: sample 11/126.50 m, Pl. 1, fig. 1
Type locality and horizon: Nieder Ochtenhausen borehole (NW Germany), Middle Miocene (reinbekian)
Diagnosis: A subspecies of Cousteaudinium aubryae with an inflated, globular to angular pericyst body, showing an irregularly bordered, patchy distribution of perforations in a gonal position. The archaeopyle has a subcircular outline.
Size: endocyst 50...54 µm, pericyst 86...98 µm.
Remarks: The subspecies is distinguished from Thalassipora species with perforated periphragm (Th. bononiensis Corradini, Th. fenestrata Liengjarern et al., Th. reticulata Morgenroth) by the patchy gonal distribution of perforations. An occasional small protuberance in an opposite position to the archaeopyle may be explained as antapical indicating an apical archaeopyle and, thus, precluding its allocation to Thalassiphora.
De Verteuil & Norris (1996) included both inflated and non-inflated specimens in their new species C. aubryae, the holotype of which is non-inflated and strongly resembles the genus Hystrichokolpoma. The stratigraphic ranges of the two morphotypes are reported to be slightly different (De Verteuil & Norris, 1996, p. 112), the latter being restricted to the earliest part of the range of the species. The inflated morphotype is the only morphotype occurring in our assemblages, indicating that the lower part of the stratigraphic range of the monospcific genus Cousteaudinium is not represented in our section. Both distinct morphology and stratigraphic range justify the erection of C. aubryae gonooperforata at subspecies level.
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