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Oligosphaeridium pulcherrimum ssp. hirsutum
Plate 7, Figures 10, 11
Holotype: Plate 7, Figures 10, 11
Type Locality: Speeton Bed C7G, early Hauterivian, inversum ammonite Zone. Holotype: Slide C7G(1), E.F. M52.4.
Derivation of Name: From the Latin hirsutus, hairy, rough, shaggy - in reference to the body ornament of this subspecies.
Diagnosis: A small subspecies of Oligosphaeridium pulcherrimum bearing a dense ornament of very short, fine spines.
Dimensions: Holotype: Central body 38x41 μm. Overall 68x84 μm
All specimens measured (5): Central body 46 (39) 35 μm × 48 (44) 41 μm.
Overall: 84 (77) 68 μm × 96 (86) 76 μm
Remarks: This is a relatively small subspecies compared to Deflandre and Cookson’s type material of O. pulcherrimum, which was quoted in Fauconier and Masure (2004, p. 401) as: Length of central body (without operculum): 47 μm. Width of central body: 61 μm. Process length: 26–38 μm.
The fine, spinose ornament of this species is similar to that of some specimens of Oligosphaeridium inordinatum n. sp., but the latter species is significantly larger and has only slightly flared and raggedly complex non-fenestrate processes. A very restricted range was observed for this subspecies at Speeton, between Beds C7G and C7C (latest early Hauterivian, inversus ammonite Zone); it was common in Bed C7G.
Holotype: Plate 7, Figures 10, 11
Type Locality: Speeton Bed C7G, early Hauterivian, inversum ammonite Zone. Holotype: Slide C7G(1), E.F. M52.4.
Derivation of Name: From the Latin hirsutus, hairy, rough, shaggy - in reference to the body ornament of this subspecies.
Diagnosis: A small subspecies of Oligosphaeridium pulcherrimum bearing a dense ornament of very short, fine spines.
Dimensions: Holotype: Central body 38x41 μm. Overall 68x84 μm
All specimens measured (5): Central body 46 (39) 35 μm × 48 (44) 41 μm.
Overall: 84 (77) 68 μm × 96 (86) 76 μm
Remarks: This is a relatively small subspecies compared to Deflandre and Cookson’s type material of O. pulcherrimum, which was quoted in Fauconier and Masure (2004, p. 401) as: Length of central body (without operculum): 47 μm. Width of central body: 61 μm. Process length: 26–38 μm.
The fine, spinose ornament of this species is similar to that of some specimens of Oligosphaeridium inordinatum n. sp., but the latter species is significantly larger and has only slightly flared and raggedly complex non-fenestrate processes. A very restricted range was observed for this subspecies at Speeton, between Beds C7G and C7C (latest early Hauterivian, inversus ammonite Zone); it was common in Bed C7G.