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Hafniasphaera delicata

Hafniasphaera delicata Fensome et al., 2009, p.34,35, pl.4, figs.l–p.

Holotype: Fensome et al., 2009, pl.4, figs.l,p.
Age: youngest occurrence, late Ypresian.

Original description: Fensome et al., 2009:
Hafniasphaera delicata sp. nov. (Plate 4, figs l-p)
HOLOTYPE. Plate 4, figs l, p; from a sidewall core sample at 1164.3 m (3820 feet) in Onondaga E-84 well; GSC type collection no. 130204, sample P37518, slide 01, co-ordinates 16.8 × 92.4, England Finder Q35/0; maximum diameter of central body 39 μm, processes up to 14 μm. The age determined for the sample from which the holotype was recovered is Seelandian-Thanetian (Late Paleocene).
ETYMOLOGY. The epithet is from the Latin 'delicatus', meaning 'dainty', in reference to the small size of speci mens of this species compared to the type and some other species of the genus.

DESCRIPTION. A species of Hafniasphaera with a spher oidal to ovoidal central body with gonal and (commonly but not invariably) sutural Spiniferites-like processes, and weakly to moderately well-developed sutural crests. Both central body wall and processes contain numerous, typic ally evenly spaced small vesicles. Vesicles commonly appear more densely distributed along sutures, and on processes are usually narrower than the breadth of the process - two or more can fit across the process - and only rarely do they cause the process sides to bulge. Specimens usually have a central body that is 35-50 μm in diameter.

SIZE. Maximum diameter of central body 38(44)55μm, length of processes up to 10(14)18; 6 specimens measured.

AGE ON SCOTIAN MARGIN. LAD: late Ypresian (Early Eo cene).
REMARKS. This species is similar to Hafniasphaera hyalospinosa and Hafniasphaera cryptovesiculata, but is smal ler; for the latter two species, which seem hard to differen tiate except by size, Hansen (1977) indicated central body diameters of 62-68 μm and 80-84 μm, respectively. Hafniasphaera hyalospinosa and Hafniasphaera cryptovesiculata also appear to have thinner, more robust walls than Hafniasphaera delicata, which encompasses most specimens of Hafniasphaera from this study of Scotian Margin material. Hafniasphaera septata tends to have vesicles that cross the entire process and cause the process walls to bulge locally; it is also usually significantly larger than Hafniasphaera delicata.
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