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Canningia grandis
Canningia grandis, Helby, 1987
Holotype: Helby, 1987, fig.30A-D
Paratypes: Helby, 1987
Locality: Australia
Age: Hauterivian
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Original description: [Helby, 1987, p. 324-325]:
Description:
Cysts lenticular with low apical horn and 2 small antapical horns, left one usually larger and located further from paracingulum than the right. Distinct protrusion of both wall layers evident at the paracingulum.
Wall layers separated; supporting structures between autophragm and endophragm generally conspicuous and significant longer in vicinity of paracingulum, apical horn and antapical horns. Ectophragm supports generally substantial, up to 9 µm long, up to 1.5 µm thick at base but thickening to 2.5 µm where they anastomose into the ectophragm. Autophragm smooth to scabrate between the ectophragm support bases and 1-2 µm thick. Ectophragm as coarse, often robust reticulum.
Paratabulation indicted by principal and occasional accessory archeoyple sutures.
Archeoyple apical, type [tA], principal suture zigzag with offset parasulcal notch. Operculum usually free.
Paracingulum usually expressed by transverse subequatorial bulge in both autophragm and ectophragm with longer ectophragmal supports (Fig.30A,B). No obvious alignment of ectophragm supports, except in paracingular region.
Parasulcus occasionally marked by fewer, small, ectophragm supports than those under surrounding paraplates resulting in a larger, less regular, reticulate, ectophragm mesh (Fig.30D).
Dimensions:
Ten specimens: A, 96-138 µm; B, 85-125 µm; C, 85-125 µm; D, 78-112 µm; E, 135-140 µm (2 specimens only); F, 130 µm (1 specimen).
Affinities: (p. 325-326):
Canningia pistica is usually smaller and shows a wider range of parasutural alignment of ectophragm supports than is evident in C. grandis. Canningia reticulata is smaller, has more delicate, densely packed, ectophragm supports and exhibits a very finely reticulate to rugoreticulate ectophragm. Canningia cf. C. reticulata of Duxbury (1977, pl.8, fig.6; pl.9, fig. 1) and Duxbury in Thusu (1978, pl.3, fig.8) may be conspecific with C. grandis.
Holotype: Helby, 1987, fig.30A-D
Paratypes: Helby, 1987
Locality: Australia
Age: Hauterivian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Helby, 1987, p. 324-325]:
Description:
Cysts lenticular with low apical horn and 2 small antapical horns, left one usually larger and located further from paracingulum than the right. Distinct protrusion of both wall layers evident at the paracingulum.
Wall layers separated; supporting structures between autophragm and endophragm generally conspicuous and significant longer in vicinity of paracingulum, apical horn and antapical horns. Ectophragm supports generally substantial, up to 9 µm long, up to 1.5 µm thick at base but thickening to 2.5 µm where they anastomose into the ectophragm. Autophragm smooth to scabrate between the ectophragm support bases and 1-2 µm thick. Ectophragm as coarse, often robust reticulum.
Paratabulation indicted by principal and occasional accessory archeoyple sutures.
Archeoyple apical, type [tA], principal suture zigzag with offset parasulcal notch. Operculum usually free.
Paracingulum usually expressed by transverse subequatorial bulge in both autophragm and ectophragm with longer ectophragmal supports (Fig.30A,B). No obvious alignment of ectophragm supports, except in paracingular region.
Parasulcus occasionally marked by fewer, small, ectophragm supports than those under surrounding paraplates resulting in a larger, less regular, reticulate, ectophragm mesh (Fig.30D).
Dimensions:
Ten specimens: A, 96-138 µm; B, 85-125 µm; C, 85-125 µm; D, 78-112 µm; E, 135-140 µm (2 specimens only); F, 130 µm (1 specimen).
Affinities: (p. 325-326):
Canningia pistica is usually smaller and shows a wider range of parasutural alignment of ectophragm supports than is evident in C. grandis. Canningia reticulata is smaller, has more delicate, densely packed, ectophragm supports and exhibits a very finely reticulate to rugoreticulate ectophragm. Canningia cf. C. reticulata of Duxbury (1977, pl.8, fig.6; pl.9, fig. 1) and Duxbury in Thusu (1978, pl.3, fig.8) may be conspecific with C. grandis.