Genus Neovermilia Day, 1961
Neovermilia ampullacea (J. de C. Sowerby, 1829)next section
Pl. 2, figs. 1-3.
Description – Medium to large sized, c. 3-10 mm in diameter. The fixed tube portion is either curved irregularly or may form a more or less regular spiral. A long free tube portion may be present and either one keel or crest or none at all. Characteristic specimens show a fine transverse ornament of granules, minute crests or wrinkles. Weak to strong annular peristomes may be present. The cross section may be triangular, especially in the posterior portion of the tube, but is more commonly circular or tunnel-shaped. The tube surface is usually bright brownish or yellowish, the tube wall commonly being thin. The base of the tube generally is cellular, the cells being distinct and short. However, nearly all features may vary considerably.
Remarks – There is a similarity between ‘Serpula’ ampullacea J. de C. Sowerby, 1829, which is the commonest species of the genus Proliserpula, and some members of the extant genus Neovermilia. Several of the species formerly assigned to Proliserpula are now considered to belong to Neovermilia.
Distribution – Vijlen to Gronsveld and Emael to Meerssen members. The total known range is late Albian to late Danian.
Neovermilia? hemmoorensis (Jäger, 1983)
Pl. 2, figs. 5, 6.
Description – Small to medium sized, maximum tube diameter 3 mm at the peristomes and 2 mm in between. Both fixed and free tube portions occur. Three small, sharp keels or, more commonly, three longitudinal lines of granules on the upper side. Commonly, one weak, narrow furrow is seen, as a result of an interruption of the transverse ornament on each lateral side. Transverse ornament consists of numerous fine (but sharper than in N. ampullacea), commonly slightly undulose, ledges. Strong, but short, rarely somewhat longer annular peristomes occur. Some specimens may lack all or some of these types of ornament. The cross section is circular, while the base of the tube usually is cellular or, less commonly, not so.
Remarks – This species displays a wider range of variation than hitherto thought. Some of the specimens identified as ‘Janita? sp.’ and ‘Proliserpula ampullacea’ by Jäger (for example, 1987, pl. 1, figs. 29, 30; pl. 2, fig. 24) more correctly belong to N.? hemmoorensis.
Distribution – Lanaye to Nekum members. Relatively common in the Lanaye Member. The total known range is late early Maastrichtian (cimbrica Zone) to late late Maastrichtian (baltica/danica Zone).