Muderongia pariata DUXBURY 1983

Holotype
Pl. 2, fig(s). 5, 8
NHM registration number: FD24(1)
 

Transmitted light images:

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Ventral face in high focus
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Optical section
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Dorsal face in low focus
 

Original diagnosis:

"A thin-walled, obviously cavate Muderongia with a smooth endophragm and a generally smooth to finely perforate periphragm. The periphragm forms one apical, two lateral and one centrally positioned antapical horn. The apical and antapical horns are distally open and are of similar length, as are the laterals, which are short, distally blunt and notched. The cyst is dorso-ventrally flattened and the body layers are in contact over much of the dorsal and ventral surfaces, but are noticeably separate around much of the periphery. Distinctly perforate areas may be observed at the horn tips and in the mid-dorsal and mid-ventral areas. The archeopyle is apical, formed by detachment of the entire apical series. Paratabulation is absent except where expressed by the archeopyle margin, by linear, finely perforate areas on the ventral surface and by the paracingulum." - From Duxbury (1983, p. 36).

Note:

This species has later been emended by Monteil (1991b, p. 474-475).

According to Århus in Århus et al. (1990, p. 191), this species is a taxonomic junior synonym of Muderongia perforata Alberti 1961. However, Monteil (1991b, p. 474 retained Muderongia pariata.

(See Williams et al., 1998).