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Canningia clathromarginata

From Fensome et al., 2019:
Canningia clathromarginata (Cookson and Eisenack, 1962b, p.495, pl.6, figs.1–4) Fensome et al., 2019a, p.21.
Holotype: Cookson and Eisenack, 1962b, pl.6, fig.2; Fauconnier and Masure, 2004, pl.17, fig.6; Fensome et al., 2019a, fig.12H.
Originally Cyclonephelium, subsequently (and now) Canningia?.
Questionable assignment: Fensome et al. (2019a, p.21).
Age: late Albian–Cenomanian.
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Cyclonephelium clathromarginatum Cookson and Eisenack, 1962

Holotype: Cookson and Eisenack, 1962, pl.6, fig.2
Age: Late Albian-Cenomanian

Original description: Cookson and Eisenack 1962b, p. 495: Cyclonephelium clathromarginatum
Shell flat, subcircular to approximately oval in plan aspect, with a circumferential border zone delimited by low and straight or fluted clathrate edges, one edge usually being more pronounced than the other. The edges are usually deepest in the antapical region and connected at wide intervals by short, narrow ridges (pl. 6, fig. 4). The sculpture of the shell varies in individual examples from finely to coarsely granular or vermiculate.

Dimensions: Holotype: 136µm broad. Range: 109-130µm long, 104-156µm broad.

Age and occurrence: (?)Upper Albian to Cenomanian: Gingin area, Wapet"s seismic shot hole Bl at 210 ft. Osborne formation, Attadale bore at 354 ft. Probably Cenomanian: Brickhouse bore (1950) at 1210 ft.

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Comments Fensome et al., 2019a:

Cookson and Eisenack (Citation1962, p. 495) described this species as follows:

Shell flat, subcircular to approximately oval in plan aspect, with a circumferential border zone delimited by low and straight or fluted clathrate edges …. The edges are usually deepest in the antapical region and connected at wide intervals by short, narrow ridges …. The sculpture of the shell varies … from finely to coarsely granular or vermiculate.

The ‘circumferential border zone’ appears to be a reflection of a distinctive peripheral holocavate structure. The type material consists of large cysts, all greater than 100 μm in length and width. We transfer this species to Canningia because it appears to be partially holocavate, but we do so questionably pending further clarification of the wall structure.

Stratigraphical occurrence. Cookson and Eisenack (Citation1962) recorded this species from the Albian to Cenomanian of Australia.
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