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Prolixosphaeridium parvispinum ssp. deirense

Prolixosphaeridium parvispinum ssp. deirense (Davey et al., 1966) Below, 1982; Emendation: Harding, 1990b, p.46–47, as Prolixosphaeridium deirense.

Now Prolixosphaeridium deirense. Originally (and now) Prolixosphaeridium deirense, subsequently Prolixosphaeridium parvispinum ssp. deirense.
Tax. jr. synonym of Hystrichosphaeridium xanthiopyxides var. parvispinum (now Prolixosphaeridium parvispinum) Deflandre, 1937, according to Davey and Verdier, 1974. Lentin and Williams, 1985 agreed with Davey and Verdier, 1974; however, Harding (1990b, p.46) retained Prolixosphaeridium parvispinum subsp. deirense (as Prolixosphaeridium deirense)

Holotype: Davey et al., 1966, pl.3, fig.2; text-fig.45
Locus typicus: Speeton Clay, West Heslerton, England
Stratum typicum: Middle Barremian

Original diagnosis: Davey et al., 1966, p.172: Prolixosphaeridium deirense
A Prolixosphaeridium having an elongate ovoidal central body bearing 60-65 processes. Processes simply or briefly bifurcate (bifurcation unequally long), closed proximally, dominantly or constantly closed distally. Two processes occupying antapical pole; remaining processes showing alignment in rows, encirceling test and offset at a position corresponding to the sulcus. Apex typically lost in archaeopyle formation; about six rows of processes present between archaeopyle and antapex, gap between third and fourth row probably corresponding to cingulum. Test surface granular and bearing dense cover of very short spinelets.

Original description: Davey et al., 1966, p.172: Prolixosphaeridium deirense
The distribution of the processes on the epitheca is into three rows; these appear to respectively comprise 9, 10, and 10 processes. Distribution of processes on the hypotheca was less easily determined. Two rows of processes were present posterior to the presumed cingulum, each apparently comprising 9 processes; and some 9 further processes clustered round the antapex, probably but not certainly representing a sixth process row.
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