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Membranilarnacia liradiscoides
Membranilarnacia liradiscoides (O. Wetzel, 1933) Downie and Sarjeant, 1965; Emendation: Marheinecke, 1992, p.116, as Membranilarnax liradiscoides.
Now Membranilarnax. Originally (and now) Membranilarnax, subsequently Membranilarnacia.
Marheinecke, 1992, emended the diagnosis of this species and retained it in Membranilarnax O. Wetzel, 1933.
Stover and Evitt, 1978, considered this to be a problematical species of Membranilarnacia.
Holotype: O. Wetzel, 1933, pl.6, fig.3 (four specimens designated).
Lectotype: O. Wetzel, 1933, pl.6, fig.3a (specimen to right, designated by Lentin and Williams, 1989)
Age: Late Cretaceous
Translation Marheinecke: GSC
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Emended description: Marheinecke 1992, p. 116: Membranilarnax liradiscoides
Cyst chorate, spheroidal to ovaloidal. Wall composed of pedium and spongy luxuria, which forms a large number of irregularly distributed processes and septa. The septa divide the cyst surface into fields. The processes rise from the septa, both at junctions and in between; they are bi- or trifurcate, and trabeculate. As a rule, a delicate supratectum is present. Areation: Indicated by the polygonal archeopyle. Archeopyle: Apical, ?(1+2+3+4), operculum secate.
Additional remark: The distinct division into fields could not be interpreted as areation. Perhaps, however, this will be possible when many specimens are studied with a SEM. Because of this uncertainty, the term "fields" is employed in the description. According to the emended generic descriptions of Membranilanarcia by WILLIAMS & DOWNIE (1966) and of Membranilarnax by SARJEANT (1985b), the character inventory of M. liradiscoides falls clearly within the generic diagnosis of Membranilarnax. The morphological similarity to the Membranilarnax pterospermoides holotype is considerable. The septa are difficult to see under a LM because of the presence of a supratectum, trabeculae and septa.
Number of specimens: > 85.
Statistics: CC diameter: 39(45)48 Ám, total diameter: 61(65)68 Ám.
Number of specimens measured: 12.
Known range: Upper Cretaceous.
Now Membranilarnax. Originally (and now) Membranilarnax, subsequently Membranilarnacia.
Marheinecke, 1992, emended the diagnosis of this species and retained it in Membranilarnax O. Wetzel, 1933.
Stover and Evitt, 1978, considered this to be a problematical species of Membranilarnacia.
Holotype: O. Wetzel, 1933, pl.6, fig.3 (four specimens designated).
Lectotype: O. Wetzel, 1933, pl.6, fig.3a (specimen to right, designated by Lentin and Williams, 1989)
Age: Late Cretaceous
Translation Marheinecke: GSC
------------------------------------------------------------------------------------------------------------------------
Emended description: Marheinecke 1992, p. 116: Membranilarnax liradiscoides
Cyst chorate, spheroidal to ovaloidal. Wall composed of pedium and spongy luxuria, which forms a large number of irregularly distributed processes and septa. The septa divide the cyst surface into fields. The processes rise from the septa, both at junctions and in between; they are bi- or trifurcate, and trabeculate. As a rule, a delicate supratectum is present. Areation: Indicated by the polygonal archeopyle. Archeopyle: Apical, ?(1+2+3+4), operculum secate.
Additional remark: The distinct division into fields could not be interpreted as areation. Perhaps, however, this will be possible when many specimens are studied with a SEM. Because of this uncertainty, the term "fields" is employed in the description. According to the emended generic descriptions of Membranilanarcia by WILLIAMS & DOWNIE (1966) and of Membranilarnax by SARJEANT (1985b), the character inventory of M. liradiscoides falls clearly within the generic diagnosis of Membranilarnax. The morphological similarity to the Membranilarnax pterospermoides holotype is considerable. The septa are difficult to see under a LM because of the presence of a supratectum, trabeculae and septa.
Number of specimens: > 85.
Statistics: CC diameter: 39(45)48 Ám, total diameter: 61(65)68 Ám.
Number of specimens measured: 12.
Known range: Upper Cretaceous.