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Hystrichosphaerina calatha

Hystrichosphaerina calatha (Sarjeant, 1961) Duxbury, 1980

Now Polystephanephorus. Originally Polystephanosphaera, subsequently (and now) Polystephanephorus, thirdly Hystrichosphaerina.
This species was retained in Polystephanephorus Sarjeant, 1961, by Lentin and Williams, 1981.

Holotype: Sarjeant, 1961, pl.14, fig.7, text-fig.7; Stancliffe and Sarjeant, 1990, pl.2, figs.1-4, text-fig.1
Locus typicus: Scarborough Castle Cliff, England
Stratum typicum: Early Oxfordian

Original diagnosis: Sarjeant, 1961, p.104: Polystephanosphaera calathus
A species of Polystephanosphaera in which the processes are solid and are arranged in circles and connected together by trabeculae in the form of a ring, each cluster of processes thus forming an open-walled and open-ended tube. It is estimated that on a complete specimen there would be twelve to sixteen such tubes, each ring trabecula borne by five to ten processes.
Dimensions: Holotype: overall diameter 88 Ám, shell diameter 45 Ám, length of process clusters c. 22 Ám. Paratype: overall diameter 90 Ám, shell diameter 45 Ám, length of process clusters c. 23 Ám.

Emended diagnosis: Stancliffe and Sarjeant, 1990, p. 205: Polystephanephorus calathus
Cyst phragmochorate, acavate anw without crests. The major paraplates are each defined by a cluster of straight, simple or distally branching processes. Processes may be interconnected medially, or may repeatedly branch. One single process per cluster bifurcates to fomm a rlng trabecula, which may be smooth or may give rise to very short spinelets. Isolate processes, distally closed and usually with bifid tips, mark the cingulum and sulcus. Paratabulation: ?4". 5"", 5c, 6""", 0p, 1"""", 4s. Surface of phragma laevigate, punctate, or infrareticulate. Archeopyle apical, type (tA); operculum free.
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