Back
Hapsocysta peridictya
Hapsocysta peridyctia (Eisenack and Cookson, 1960, p.8, pl.3, figs.5–6) Davey, 1979b, p.556. Emendation: Davey, 1979b, p.556, as Hapsocysta peridictya.
Originally Cannosphaeropsis, subsequently Cannosphaeropsis?, thirdly (and now) Hapsocysta.
Holotype: Eisenack and Cookson, 1960, pl.3 fig.6; Fensome et al., 1995, fig.2 — p.1661; Heilmann-Clausen and Van Simaeys, 2005, text-figs.6A–B.
Locus typicus: Carnarvon Basin, W Australia
Stratum typicum: Late Albian-Cenomanian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hapsocysta peridictya (Eisenack and Cookson, 1960) Davey, 1979b. According to Davey (1979b), this species has a relatively small, thin-walled endocyst, which is almost completely surrounded by a large subspherical wide-meshed, net-like structure. The bipartite strands of the net are smooth to lightly granular and generally closely adhere to each other. Where branching, the two strands tend to diverge and a very fine membrane is seen to connect them. The archeopyle is uncertain. Size: overall 76-114 µm, capsule 43-48 µm.
--------------------------------------------------
Original description: Eisenack and Cookson, 1960, p. 8: Cannosphaeropsis peridyctia
Shell sphaerical, thin-walled, completely enveloped in a wide-meshed network the threads of which are thin, cylindrical or occasionally flat. The supporting threads so evident in other species of Cannosphaeropsis are not clearly defined and usually the greater portion of the net is free from the shell.
Dimensions: Type: diameter of the shell c.43 µm, overall diameter c.76 µm.
-------------------------------------
Emended diagnosis: Davey 1979b, p. 556-557
A species of Hapsocysta having a relatively small, thin-walled endocyst which is almost completely surrounded by a large subsphencal, wide-meshed, net-like structure. The bipartite strands of the net are smooth to lightly granular and generally closely adhere to each other. Where branching, the two strands tend to diverge and a very fine membrane is seen to connect them. An archeopyle is probably normally developed but is difficult to observe.
Description: Davey 1979b, p. 556-557
The bipartite strands of the net are partly hollow in some specimens but this feature is usually difficult to discern. Rarely, fine ridges occur on the endocyst and these probably partly define a tabulation. The thin-walled endocyst is typically distorted which makes onentation by archeopyle position extremely difficult. However, the small meshes of the parasulcal region (Pl. 4, Fig. 2, 5) are usually obvious and may be related to the elongate paracingular meshes (Pl. 4, Fig. 4) thus aiding in orientation
synonym: Davey 1979b, p. 556-557
1958 Cannosphaeropsis fenestrata Deflandre and Cookson, p. 46, pl. 7, hg. 1-3.
1960 C. peridictya Eisenack and Cookson, p. 8, pl. 3, fig. 5, 6.
Originally Cannosphaeropsis, subsequently Cannosphaeropsis?, thirdly (and now) Hapsocysta.
Holotype: Eisenack and Cookson, 1960, pl.3 fig.6; Fensome et al., 1995, fig.2 — p.1661; Heilmann-Clausen and Van Simaeys, 2005, text-figs.6A–B.
Locus typicus: Carnarvon Basin, W Australia
Stratum typicum: Late Albian-Cenomanian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hapsocysta peridictya (Eisenack and Cookson, 1960) Davey, 1979b. According to Davey (1979b), this species has a relatively small, thin-walled endocyst, which is almost completely surrounded by a large subspherical wide-meshed, net-like structure. The bipartite strands of the net are smooth to lightly granular and generally closely adhere to each other. Where branching, the two strands tend to diverge and a very fine membrane is seen to connect them. The archeopyle is uncertain. Size: overall 76-114 µm, capsule 43-48 µm.
--------------------------------------------------
Original description: Eisenack and Cookson, 1960, p. 8: Cannosphaeropsis peridyctia
Shell sphaerical, thin-walled, completely enveloped in a wide-meshed network the threads of which are thin, cylindrical or occasionally flat. The supporting threads so evident in other species of Cannosphaeropsis are not clearly defined and usually the greater portion of the net is free from the shell.
Dimensions: Type: diameter of the shell c.43 µm, overall diameter c.76 µm.
-------------------------------------
Emended diagnosis: Davey 1979b, p. 556-557
A species of Hapsocysta having a relatively small, thin-walled endocyst which is almost completely surrounded by a large subsphencal, wide-meshed, net-like structure. The bipartite strands of the net are smooth to lightly granular and generally closely adhere to each other. Where branching, the two strands tend to diverge and a very fine membrane is seen to connect them. An archeopyle is probably normally developed but is difficult to observe.
Description: Davey 1979b, p. 556-557
The bipartite strands of the net are partly hollow in some specimens but this feature is usually difficult to discern. Rarely, fine ridges occur on the endocyst and these probably partly define a tabulation. The thin-walled endocyst is typically distorted which makes onentation by archeopyle position extremely difficult. However, the small meshes of the parasulcal region (Pl. 4, Fig. 2, 5) are usually obvious and may be related to the elongate paracingular meshes (Pl. 4, Fig. 4) thus aiding in orientation
synonym: Davey 1979b, p. 556-557
1958 Cannosphaeropsis fenestrata Deflandre and Cookson, p. 46, pl. 7, hg. 1-3.
1960 C. peridictya Eisenack and Cookson, p. 8, pl. 3, fig. 5, 6.