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Dinopterygium perforatum
Dinopterygium perforatum Clarke and Verdier, 1967; Emendations: Davey and Verdier, 1971, p.30, as Pterodinium perforatum; Below, 1981a, p.23-24 and Masure, 1988a, p.363-364, both as Maghrebinia perforata.
Now Atopodinium. Originally Dinopterygium, subsequently Pterodinium, thirdly Pterodinium?, fourthly Maghrebinia, fifthly (and now) Atopodinium.
Holotype: Clarke and Verdier, 1967, pl.6, figs.1-2; Masure, 1988, pl.1, figs.1-9, text-figs.1a-b
Locus typicus: Southern Cliff, Isle of Wight, England
Stratum typicum: Early Cenomanian
Original diagnosis: Clarke and Verier, 1967, p.37
A species of Dinopterygium with an indistinct girdle marked on the outline by two protrusions, and ledges which are perforate.
Original description: Clarke and Verdier, 1967, p.37
The epitheca is smaller than the hypotheca. Sides of epitheca straight; a small horn is sometimes observed at the apex. Sides of hypotheca straight; antapex rounded. Girdle indicated on outline only by the presence of two protrusions (pl. 6, fig. 2). Tabulation present, distinct and similar in arrangement to that of Scriniodinium. Plates bordered by high ledges 6-12 Ám high, sculptured by perforations of various sizes. The form of the ledges is irregular, sometimes being high and entire, but often there is a development of processes of irregular width and height, generally perforated and with expanded tops. In this latter case the processes join at their bases to form low perforate ledges. The plates are mostly smooth except for a small perforated area adjacent to the ledges. No definite archaeopyle has so far been observed.
Measurements:HolotypeRange
Length66 Ám60-90 Ám
Breadth71 Ám60-84 Ám
Height of ledges (max.)11 Ám6-12 Ám
Affinities:
Clarke and Verdier, 1967, p.37: D. perforatum differs from D. cladoides in the presence of perforated ledges, and the absence of verrucae on the plates.
Now Atopodinium. Originally Dinopterygium, subsequently Pterodinium, thirdly Pterodinium?, fourthly Maghrebinia, fifthly (and now) Atopodinium.
Holotype: Clarke and Verdier, 1967, pl.6, figs.1-2; Masure, 1988, pl.1, figs.1-9, text-figs.1a-b
Locus typicus: Southern Cliff, Isle of Wight, England
Stratum typicum: Early Cenomanian
Original diagnosis: Clarke and Verier, 1967, p.37
A species of Dinopterygium with an indistinct girdle marked on the outline by two protrusions, and ledges which are perforate.
Original description: Clarke and Verdier, 1967, p.37
The epitheca is smaller than the hypotheca. Sides of epitheca straight; a small horn is sometimes observed at the apex. Sides of hypotheca straight; antapex rounded. Girdle indicated on outline only by the presence of two protrusions (pl. 6, fig. 2). Tabulation present, distinct and similar in arrangement to that of Scriniodinium. Plates bordered by high ledges 6-12 Ám high, sculptured by perforations of various sizes. The form of the ledges is irregular, sometimes being high and entire, but often there is a development of processes of irregular width and height, generally perforated and with expanded tops. In this latter case the processes join at their bases to form low perforate ledges. The plates are mostly smooth except for a small perforated area adjacent to the ledges. No definite archaeopyle has so far been observed.
Measurements:HolotypeRange
Length66 Ám60-90 Ám
Breadth71 Ám60-84 Ám
Height of ledges (max.)11 Ám6-12 Ám
Affinities:
Clarke and Verdier, 1967, p.37: D. perforatum differs from D. cladoides in the presence of perforated ledges, and the absence of verrucae on the plates.