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Hystrichosphaeridium tubiferum ssp. tubiferum

Hystrichosphaeridium tubiferum ssp. tubiferum (Ehrenberg, 1837b) Deflandre, 1937; emend. Davey and Williams, 1966

Autonym.
Holotype: Ehrenberg 1838, pl.1, fig.16; Lejeune-Carpentier, 1940, fig.1; Davey and Williams, 1966, pl.6, fig.1-2
Paratype: ?Ehrenberg, 1938, mentioned in Davey and Williams, 1966, p. 56
Locus typicus: Delitzsch flint
Stratum typicum: ?Late Cretaceous
Translations Wetzel, 1933, Lejeune-Carpentier, 1940 and Rossignol, 1964 : LPP

Original diagnosis: ?Ehrenberg, 1838: Xanthidium tubiferum

Diagnosis: O. Wetzel, 1933, p. 40: Hystrichosphaera tubifera
Shell spherical, 10-20 processes, mostly large and strong, tubiform, distally widened into a crown or saucer (comparable to the funnel or mouthpiece of a trumpet). Individual processes may be less strong and distally ornamented with only a few teeth.
Dimensions: diameter of shell 36-40 Ám, with processes 64-72 Ám, processes 16-20 Ám.

Lejeune-Carpentier, 1940, p. B218
(annotated)...Hystrichosphaeridium tubiferum is a species with a a relatively large ellipsoidal shell. In the holotype we observe a diameter of about 33 Ám; however, the other specimens may well exceed 40 Ám. The specimen we depict measures about 38 Ám. the tubes are quite numerous, about thirty on the most complete specimens we studied. The length of the tubes does not attain the diameter of the shell. Their dimensions are unequal: some are slender, others quite robust. The base of attachment of the tubes on the shell, forming a pedestal, is large and polygonal. The distal extremity opens into a funnel; the recurved rims are extended into some lobes with pointed extremities.

Rossignol, 1964, p. 89
The test is spherical, without visible tabulation; its wall is thin, its surface smooth. The archaeopyle presents a polygonal outline. The processes, few in number, are regularly distributed, and do not permit an orientation of the specimen; long, thin, tubular, erect, they widen at the base and at the tip, terminating in an open funnel, bordere by thin, more or less well-developed hooks. As always, only the outer layer of the test contributes to the processes.
Dimensions: test 35-50 Ám, processes appr. 15 Ám.

Emended diagnosis: Davey and Williams, 1966, p. 56-57
Central body spherical to subspherical, smooth or slightly granular wall composed of two layers. Processes well developed, tubiform, open distally with entire or serrate circular margin. Processes give a reflected tabulation of 4-5", 6"", 6c, 5-6""", 1p, 1"""" and a variable number of sulcal plates, commonly 4-5. Apical archaeopyle usually present.
Description: Central body composed of thin smooth endophragm and smooth or slightly granular periphragm, the latter also forming the processes. The processes are tubiform with distally a denticulate to serrate circular margin. At the base of each process is a characteristic circular mark caused by the initial divergence of the endophragm and the periphragm. The processes, up to 30 in number, are usually shorter in length than the small diameter of the central body. They are of unequal width, the sulcal processes being finer and usually shorter. Lejeune-Carpentier (1940), after examination of the type material, records that this species is common from the Upper Turonian and Senonian.

Supplemental description: Hultberg, 1985, p. 133
Chorate cyst, composed of endophragm and periphragm, appressed between processes. The surface of the endophragm is smooth to slightly granulate. The surface of the periphragm is smooth. The shape of the cyst is elongate ellipsoidal.
Paratabulation is clearly expressed by intratabular processes. These are hollow, cylindrical, and distally open. The process-bases are circular or, in the paracingulum, ellipsoidal. The process-tips are trumpet-shaped, sometimes with slightly digitate margins. The paratabulation is gonyaulacacean, process-formula:
1pr, 4", 6"", 6c, 1p, 6""", 1"""". The archeopyle is apical, type tA. Operculum free.
Paracingulum is indicated by six flattened processes, indicating six paracingular paraplates. Parasulcus is indicated by four slender processes, indicating four
parasulcal paraplates.
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