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Tityrosphaeridium exilimurum

Tityrosphaeridium? exilimurum (Davey and Williams, 1966) Jain and Garg, 1986

Originally Cordosphaeridium, subsequently Hystrichosphaerina?, thirdly Tityrosphaeridium?.
Questionable assignment: Jain and Garg (1986a, p.120).
Taxonomic senior synonym: Cordosphaeridium fibrospinosum, according to Fensome et al. (2009, p.23).
Taxonomic junior synonym: Achomosphaera (subsequently Cordosphaeridium) valianta, according to Jain (1982, p.52).

Holotype: Davey and Williams, 1966, pl.11, fig.2; Bujak et al., 1980, pl.7, figs.4-5
Age: Early Eocene

Original diagnosis: Davey and Williams, 1966, p. 87-88
Ovoidal central body, composed of thin, smooth or slightly granular endophragm with fine fibrils of periphragm running over surface. Processes tubiform or buccinate, of variable width, and rarely latispinous, distally open with serrate or undulose margin. Wall of processes thin and often fenestrate.
Dimensions: holotype: diameter of central body 44x54 µm, length of processes 18-26 µm. Range: diameter of central body 44-98 µm, length of processes 16-42 µm.

Original description: Davey and Williams, 1966, p.88
Haplotabular archaeopyle and tabulation characteristic of the genus Cordosphaeridium. The number of processes per plate area is one, but occasionally a fine subsidiary process may be present. Fine processes also occur in the sulcal region. Both the endophragm and periphragm are extremely thin, especially the latter when forming the processes. The wall of the processes is smooth or fibrous; in the former the fibrils are only faintly developed. Whether or not the processes are always fenestrate is difficult to determine, even at high magnification, on account of the thinness of the periphragm. The processes rarely exceed half the diameter of the central body; they are up to 10 µm wide meridionally and distally extremely expanded. Adjacent processes are occasionally united distally.

Affinities:
Davey and Williams, 1966, p. 88: No other described species possesses fine, often perforate processes with an apical haplotabular archaeopyle and tabulation 1", 6", 6c, 6""", 1"""" and a variable number of sulcal processes. ?C. cantharellum (Brosius 1963) is similar in general form but possesses stronger, more cylindrical processes which are never perforate or united distally, and often have a recurved distal margin.
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