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Membranilarnax liradiscoides
From Fensome et al., 2019:
Membranilarnax liradiscoides Wetzel, 1933b, p.52–53, pl.6, figs.3a–b. Emendation: Marheinecke, 1992, p.116, as Membranilarnax liradiscoides. Holotype: not designated. Lectotype: Wetzel, 1933b, pl.6, fig.3a (specimen to right), designated by Lentin and Williams (1989, p.239). Originally (and now) Membranilarnax, subsequently Membranilarnacia, thirdly Membranilarnacia?. Marheinecke (1992, p.116) retained this species in Membranilarnax. Age: Late Cretaceous.
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Emendation Marheinecke, 1992, p. 116-117 (translated from German):
Emended description: Cyst chorate, spheroidal to ovaloidal. Wall composed of pedium and cancellous luxuria, forming a large number of irregularly distributed processes and septa. The septa form a pleural pattern on the cyst surface. The processes arise from the septa both at the points of contact and in between; they are bi- or trifurcate, trabeculate. A delicate supratectum is usually present. Areation: indicated by the polygonal archeopyle. Archeopyle: apical, ?(1+2+3+4), secant operculum.
Additional note: The well-developed fielding could not be interpreted as areation. Perhaps, however, this will be possible upon examination of many specimens under the SEM. Because of this uncertainty, the term "fielding" is used in the description. According to the emended descriptions of the genera Membranilanarcia and Membranilarnax by Williams & Downie (1966) and Sarjeant (1985b), respectively, the character inventory of M. liradiscoides clearly falls within the genus diagnosis of Membranilarnax. The morphological proximity to the holotype Membranilarnax pterospermoides is close. The present septa are difficult to recognize in the light microscope, as the presence of the supratectum, trabeculae, and septa complicates interpretation.
Specimens: >85.
Statistics: Diameter of the central capsule: 39(45)48; total diameter: 61(65)68.
Measured specimens: 12.
Known range: Late Cretaceous.
Membranilarnax liradiscoides Wetzel, 1933b, p.52–53, pl.6, figs.3a–b. Emendation: Marheinecke, 1992, p.116, as Membranilarnax liradiscoides. Holotype: not designated. Lectotype: Wetzel, 1933b, pl.6, fig.3a (specimen to right), designated by Lentin and Williams (1989, p.239). Originally (and now) Membranilarnax, subsequently Membranilarnacia, thirdly Membranilarnacia?. Marheinecke (1992, p.116) retained this species in Membranilarnax. Age: Late Cretaceous.
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Emendation Marheinecke, 1992, p. 116-117 (translated from German):
Emended description: Cyst chorate, spheroidal to ovaloidal. Wall composed of pedium and cancellous luxuria, forming a large number of irregularly distributed processes and septa. The septa form a pleural pattern on the cyst surface. The processes arise from the septa both at the points of contact and in between; they are bi- or trifurcate, trabeculate. A delicate supratectum is usually present. Areation: indicated by the polygonal archeopyle. Archeopyle: apical, ?(1+2+3+4), secant operculum.
Additional note: The well-developed fielding could not be interpreted as areation. Perhaps, however, this will be possible upon examination of many specimens under the SEM. Because of this uncertainty, the term "fielding" is used in the description. According to the emended descriptions of the genera Membranilanarcia and Membranilarnax by Williams & Downie (1966) and Sarjeant (1985b), respectively, the character inventory of M. liradiscoides clearly falls within the genus diagnosis of Membranilarnax. The morphological proximity to the holotype Membranilarnax pterospermoides is close. The present septa are difficult to recognize in the light microscope, as the presence of the supratectum, trabeculae, and septa complicates interpretation.
Specimens: >85.
Statistics: Diameter of the central capsule: 39(45)48; total diameter: 61(65)68.
Measured specimens: 12.
Known range: Late Cretaceous.