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Scriniodinium pharo

Scriniodinium pharo (Duxbury, 1977) Davey, 1982

Originally Endoscrinium, subsequently (and now) Scriniodinium. Jan du Chêne et al. (1986a, p.316) and Woollam and Riding (1983, p.7) also proposed this combination.
Lentin and Williams, 1985 retained this species in Endoscrinium (Klement, 1960) Vozzhennikova, 1967. Jan du Chêne et al., 1986 agreed with Davey, 1982, but Lentin and Williams, 1989 followed Lentin and Williams, 1985. Woollam and Riding, 1983 also effected the transfer of this species to Scriniodinium.

Holotype: Duxbury, 1977, pl.9, fig.5; Jan du Chêne et al., 1986, pl.111, figs.11-12
Locus typicus: Speeton Clay, Speeton, England.
Stratum typicum: Valanginian

Original diagnosis: Duxbury, 1977, p. 32: Endoscrinium pharo
A thin-walled, fairly large, cavate cyst. Periblast smooth to finely granular and apically produced into a characteristically long, distally open horn which tapers towards the apex. Endoblast smooth, ovoidal, longer than broad and with a prominent, bluntly-rounded apical prominence. A faint tabulation is outlined on the periphragm by narrow, low, smooth ridges. Tabulation ?4", 6", 5""", ?1pv, ?"""". Archeopyle precingular, formed by loss of plate 3". Sometimes an additional opening occurs in the periphragm, possibly corresponding to 1 pv.
Observed Dimensions: Holotype 119 x 70 µm. Overall 141(121)90 x 78(70)57 µm.

Affinities: Duxbury, 1977, p. 32: Endoscrinium pharo
In possessing a distinct apical horn and in the general shape of the test other than the apical horn, Endoscrinium pharo resembles Endoscrinium campanula (Gocht) Vozzhennikova. The main difference between the two is the degree of development of the apical horn. That of E. pharo is always very well-developed (usually about 40 microns long) as opposed to the short horn of E. campanula. The difference in horn length between these two species results in a considerable difference in the average overall length of the test.
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