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Resticulasphaera medusae
Resticulasphaera *medusae Harding, 1990b, p.44–45, pl.27, figs.1–8 ex Harding in Williams et al. 1998, p.526. Holotype: Harding, 1990b, pl.27, fig.1. This name was not validly published in Harding (1990b) since the lodgement of the holotype was not specified (I.C.N. Article 40.7). Age: late Hauterivian–late Barremian.
Original diagnosis: Harding, 1990, p. 44
Shape: Ambitus subcircular to prolate ovoidal. Epicyst about 1/3 of cyst length, the remaining 2/3 consisting largely of hypocyst (paracingulum narrow). Greatest width immediately post-cingulum. Strong dorso-ventral compression.
Phragma: Autophragm 0.3-0.5 µm thick. Surface sculpture of fine interwoven, matted fibres up to 2 µm long, forming a dense cover over the whole cyst save for the paracingulum which often verges on laevigate (Plate 27, Fig. 4). Acuminate processes in the form of long (up to 10 µm), solid, hair-like fibres. These are apparently partially non-tabular and partially sutural (along the borders of the paracingulum) in location.
ParatabuIation: Not discernable save for the differentiation of the paracingulum.
Archaeopyle: Type E, entire epicyst lost as simple, free, polyplacoid operculum, which may rarely remain attached to the parasulcal region.
Paracingulum: Indicated by the subdued nature of the sculpture as a narrow equatorial band. Anterior edge of paracingulum becomes rolled over towards the antapex after archaeopyle formation.
Parasulcus: Undifferentiated, only determinable when the epicyst remains attached to this region.
Dimensions: Body length (22) 18.7 (17) µm. Body width (18) 16.9 (15) µm. Process length (14) 7 (5) µm.
Original diagnosis: Harding, 1990, p. 44
Shape: Ambitus subcircular to prolate ovoidal. Epicyst about 1/3 of cyst length, the remaining 2/3 consisting largely of hypocyst (paracingulum narrow). Greatest width immediately post-cingulum. Strong dorso-ventral compression.
Phragma: Autophragm 0.3-0.5 µm thick. Surface sculpture of fine interwoven, matted fibres up to 2 µm long, forming a dense cover over the whole cyst save for the paracingulum which often verges on laevigate (Plate 27, Fig. 4). Acuminate processes in the form of long (up to 10 µm), solid, hair-like fibres. These are apparently partially non-tabular and partially sutural (along the borders of the paracingulum) in location.
ParatabuIation: Not discernable save for the differentiation of the paracingulum.
Archaeopyle: Type E, entire epicyst lost as simple, free, polyplacoid operculum, which may rarely remain attached to the parasulcal region.
Paracingulum: Indicated by the subdued nature of the sculpture as a narrow equatorial band. Anterior edge of paracingulum becomes rolled over towards the antapex after archaeopyle formation.
Parasulcus: Undifferentiated, only determinable when the epicyst remains attached to this region.
Dimensions: Body length (22) 18.7 (17) µm. Body width (18) 16.9 (15) µm. Process length (14) 7 (5) µm.