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Kisselovia crassiramosa
Kisselovia crassiramosa (Williams and Downie, 1966) Damassa, 1979
Now Charlesdowniea crassiramosa. Originally Wetzeliella tenuivirgula var. crassiramosa, subsequently Wetzeliella tenuivirgula ssp. crassiramosa, thirdly Kisselovia tenuivirgula ssp. crassiramosa, fourthly Kisselovia crassiramosa, fifthly (and now) Charlesdowniea crassiramosa.
The taxon was raised to subspecies status by Lentin and Williams, 1973. The elevation of this taxon to species status is not attributable to Costa and Downie, 1979.
Holotype: Williams and Downie, 1966, pl.19, fig.7
Locus typicus: Whitecliff, England
Stratum typicum: Early Eocene
Original description: Williams and Downie, 1966, p. 189: Wetzeliella (Wetzeliella) tenuivirgula var. crassiramosa
This differs from the typical W. tenuivirgula in the nature of the distal branching of the processes; the secae and trabeculae are much wider and taeniate, the reticulum being much stronger as a result. The processes forming the simulate complexes are often united by particularly wide taeniate secae (or bars) up to 3Á in width. Frequently there are simple unconnected spines with blunt or bulbous terminations branching off from the bars and trabeculae. In outline, the outer shell lies between that of W. articulata and W. symmetrica, individuals with an outline approaching the latter species predominating.
Holotype: outer shell length 125 Ám; breadth 122 Ám. Capsule--length 80 Ám; breadth 71 Ám. Observed range: outer shell length 125-182 Ám; breadth 122-160 Ám; Capsule, length 80-144 Ám; breadth 71-103 Ám.
Supplemental diagnosis: Damassa, 1979, p. 837
Peridinioid cyst characterized bv a network of intersecting trabeculae supported by processes confined mainly to penitabular rows. Trabeculae about equal to processes in thickness. Paratabulation defined by parasutural interruptions in the network.
Supplemental description: Damassa, 1979, p. 837-838
A distinctive species of Kisselovia characterized by a network of intricately intersecting trabeculae supported by processes confined mainly to penitabular rows. Trabeculae approximately equal in thickness to the processes (1 Ám). Parasutural interruptions in the network define the paratabulation, but networks of adjacent paraplates may be connected by trabeculae which cross the parasutural areas. Pericyst, length 121-154 Ám, mean = 138 Ám, width 110-148 Ám, mean 127 Ám; endocyst, length 64-105 Ám, mean 75 Ám, width 62-100 Ám, mean = 75 Ám; 21 specimens measured. Periphragm rhomboidal in outline, forming distinct horns at apex, antapex and paracingulum. Endophragm also rhomboidal but with decidedly rounded corners beneath pericoels and horns. Four pericoels formed by separation of periphragm and endophragm at horns. Processes are 8-13 Ám in height (mean = 9.5 Ám, of 21 specimens), and reach their maximum height between horns. The process-trabeculae complexes delineate a complete peridinioid paratabulation. Specimens are dorsoventrally compressed, so that paraplates 2", 4", 2" and 4", located on the "edges" of the cyst, are very narrow and thus rarely seen. Paracingulum indicated by a narrow band of processes and trabeculae, which form a series of interconnected loops. Endo- and periarcheopyle may be of similar size but endoarcheopyle is commonly smaller than periarcheopyle. Periarcheopyle conspicuously elongate in some specimens (Pl. 8, fig. 8). Opercula for both endo- and periarcheopvle simple, free. Perioperculum bears processes and trabeculae (Pl. 8, fig. 7). The right antapical horn is greatly reduced with respect to the left, and may be almost lacking in some specimens. Paratabulation.--4", 7", xc, 3-4s, 5""", 2"""". Inferred thecal tabulation.--as above.
Now Charlesdowniea crassiramosa. Originally Wetzeliella tenuivirgula var. crassiramosa, subsequently Wetzeliella tenuivirgula ssp. crassiramosa, thirdly Kisselovia tenuivirgula ssp. crassiramosa, fourthly Kisselovia crassiramosa, fifthly (and now) Charlesdowniea crassiramosa.
The taxon was raised to subspecies status by Lentin and Williams, 1973. The elevation of this taxon to species status is not attributable to Costa and Downie, 1979.
Holotype: Williams and Downie, 1966, pl.19, fig.7
Locus typicus: Whitecliff, England
Stratum typicum: Early Eocene
Original description: Williams and Downie, 1966, p. 189: Wetzeliella (Wetzeliella) tenuivirgula var. crassiramosa
This differs from the typical W. tenuivirgula in the nature of the distal branching of the processes; the secae and trabeculae are much wider and taeniate, the reticulum being much stronger as a result. The processes forming the simulate complexes are often united by particularly wide taeniate secae (or bars) up to 3Á in width. Frequently there are simple unconnected spines with blunt or bulbous terminations branching off from the bars and trabeculae. In outline, the outer shell lies between that of W. articulata and W. symmetrica, individuals with an outline approaching the latter species predominating.
Holotype: outer shell length 125 Ám; breadth 122 Ám. Capsule--length 80 Ám; breadth 71 Ám. Observed range: outer shell length 125-182 Ám; breadth 122-160 Ám; Capsule, length 80-144 Ám; breadth 71-103 Ám.
Supplemental diagnosis: Damassa, 1979, p. 837
Peridinioid cyst characterized bv a network of intersecting trabeculae supported by processes confined mainly to penitabular rows. Trabeculae about equal to processes in thickness. Paratabulation defined by parasutural interruptions in the network.
Supplemental description: Damassa, 1979, p. 837-838
A distinctive species of Kisselovia characterized by a network of intricately intersecting trabeculae supported by processes confined mainly to penitabular rows. Trabeculae approximately equal in thickness to the processes (1 Ám). Parasutural interruptions in the network define the paratabulation, but networks of adjacent paraplates may be connected by trabeculae which cross the parasutural areas. Pericyst, length 121-154 Ám, mean = 138 Ám, width 110-148 Ám, mean 127 Ám; endocyst, length 64-105 Ám, mean 75 Ám, width 62-100 Ám, mean = 75 Ám; 21 specimens measured. Periphragm rhomboidal in outline, forming distinct horns at apex, antapex and paracingulum. Endophragm also rhomboidal but with decidedly rounded corners beneath pericoels and horns. Four pericoels formed by separation of periphragm and endophragm at horns. Processes are 8-13 Ám in height (mean = 9.5 Ám, of 21 specimens), and reach their maximum height between horns. The process-trabeculae complexes delineate a complete peridinioid paratabulation. Specimens are dorsoventrally compressed, so that paraplates 2", 4", 2" and 4", located on the "edges" of the cyst, are very narrow and thus rarely seen. Paracingulum indicated by a narrow band of processes and trabeculae, which form a series of interconnected loops. Endo- and periarcheopyle may be of similar size but endoarcheopyle is commonly smaller than periarcheopyle. Periarcheopyle conspicuously elongate in some specimens (Pl. 8, fig. 8). Opercula for both endo- and periarcheopvle simple, free. Perioperculum bears processes and trabeculae (Pl. 8, fig. 7). The right antapical horn is greatly reduced with respect to the left, and may be almost lacking in some specimens. Paratabulation.--4", 7", xc, 3-4s, 5""", 2"""". Inferred thecal tabulation.--as above.