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Oligokolpoma tubulus
Oligokolpoma tubulus Fensome et al., 2009, p.47, pl.7, figs.m–o,q–t. Holotype: Fensome et al., 2009, pl.7, figs.m–o. N.I.A. Age: youngest occurrence, early Serravallian.
Original description (Fensome et al., 2009)
Holotype. Plate 7, figs m-o; from a cuttings sample at 744–753 m (2440-2470 feet) in Wenonah J-75 well; GSC
type collection no. 130258, sample P1 3480, slide 09, coordinates 17.6 × 90.0, England Finder R33/1; maximum diameter of central body 58 μm, length of horns up to 38 μm. The age determined for the sample from which the holotype was recovered is Middle Miocene; however, since it is a cuttings sample and no FAD has been determined for the species, the holotype is a specimen possibly caved down well from a younger stratum.
Etmology. The epithet is from the Latin 'tubulus', meaning 'little pipe', in reference to the large, pipe-like pre and
postcingular and antapical processes. It is a noun in apposition and thus its ending should not be changed to agree with the gender of the generic name.
Description. A species of Oligokolpoma with mostly broad, tube-like, apparently open pre and postcingular
processes with concave sides and aculeate to digitate endings; and a larger antapical processes that may be similar
in shape to the typical pre and postcingular processes or may have convex sides. Smaller and narrower processes may be present in or around the sulcus (for example, representing the 6" plate).
Size. Maximum diameter of central body 58(64)70μm, length of horns up to 27(36)44μm; 3 specimens measured.
Age on Scotland margin. LAD: early Serravallian (Middle Miocene).
Remarks. This species is similar to Hystrichokolpoma rigaudiae but lacks cingular and (generally) sulcal processes.
It differs from the type of the invalidly-named species Hystrichokolpoma reductum of Zevenboom & Santarelli in the
nature of the processes: those of the latter are stubbier and tend to have straight or convex sides, somewhat similar to the processes of Hystrichokolpoma cinctum. The process formula for the type of Oligokolpoma tubulus appears to be: x',6", 1as, 0c, 5'", 1ps, 1"". No opercula, isolated or in place have been found and, hence, the nature and distribution of the apical processes is unknown. From comparison with similar taxa, we would predict the presence of four relatively small processes. See also the discussion under Cousteaudinium.
Original description (Fensome et al., 2009)
Holotype. Plate 7, figs m-o; from a cuttings sample at 744–753 m (2440-2470 feet) in Wenonah J-75 well; GSC
type collection no. 130258, sample P1 3480, slide 09, coordinates 17.6 × 90.0, England Finder R33/1; maximum diameter of central body 58 μm, length of horns up to 38 μm. The age determined for the sample from which the holotype was recovered is Middle Miocene; however, since it is a cuttings sample and no FAD has been determined for the species, the holotype is a specimen possibly caved down well from a younger stratum.
Etmology. The epithet is from the Latin 'tubulus', meaning 'little pipe', in reference to the large, pipe-like pre and
postcingular and antapical processes. It is a noun in apposition and thus its ending should not be changed to agree with the gender of the generic name.
Description. A species of Oligokolpoma with mostly broad, tube-like, apparently open pre and postcingular
processes with concave sides and aculeate to digitate endings; and a larger antapical processes that may be similar
in shape to the typical pre and postcingular processes or may have convex sides. Smaller and narrower processes may be present in or around the sulcus (for example, representing the 6" plate).
Size. Maximum diameter of central body 58(64)70μm, length of horns up to 27(36)44μm; 3 specimens measured.
Age on Scotland margin. LAD: early Serravallian (Middle Miocene).
Remarks. This species is similar to Hystrichokolpoma rigaudiae but lacks cingular and (generally) sulcal processes.
It differs from the type of the invalidly-named species Hystrichokolpoma reductum of Zevenboom & Santarelli in the
nature of the processes: those of the latter are stubbier and tend to have straight or convex sides, somewhat similar to the processes of Hystrichokolpoma cinctum. The process formula for the type of Oligokolpoma tubulus appears to be: x',6", 1as, 0c, 5'", 1ps, 1"". No opercula, isolated or in place have been found and, hence, the nature and distribution of the apical processes is unknown. From comparison with similar taxa, we would predict the presence of four relatively small processes. See also the discussion under Cousteaudinium.