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Hystrichosphaeridium dowlingii

Hystrichosphaeridium dowlingii Harland 1973

Holotype: Harland, 1973, pl.85, fig.1; Fauconnier and Masure, 2004, pl.44, fig.7.
Locus typicus: Southern Alberta, Canada
Stratum typicum: Late Campanian

Original diagnosis: Harland, 1973, p. 681
Chorate cyst, spheroidal in shape, made up of periphragm and endophragm. Test microgranulate. Tabulation 6", 6c, 6""", 1-2p, 1"""". Processes hollow slender to latispinous, erect to curved, cylindrical, distally flared and fenestrate. Archeopyle of the A type.
Dimensions. Holotype: Long axis of cyst 44.0 Ám; short axis of cyst 38.0 Ám, processes range in length from 15 to 24. Range: Long axis of cyst 25.0 (34.4) 46.0 Ám; short axis of cyst 29.0 (34.0) 54.0 Ám, processes range in length from 10 to 28 Ám. Twelve specimens measured, the number of specimens studied.

Original description: Harland, 1973, p. 681
The periphragm makes up the processes which do not appear to connect to the interior of the cyst. Test "ornament" does not extend on to the process shafts. The sulcal area devoid of all processes except for a group of two sulcal processes. A sulcal notch may also be seen in some specimens.

Affinities:
Harland, 1973, p. 681: This species is easily distinguishable from H. cf. arborispinum by the nature of the processes, i.e. fenestrate nature and lack of "ornamentation" on the processes shafts. The test "ornamentation" is also much coarser than that of H. cf. arborispinum. Its affinities are gonyaulacacean with the hystrichosphaeridioid lineage.
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