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Serpula? trilineata Roemer, 1841
Pl. 2, fig. 4.
Description – Medium sized; only with the fixed tube portion present. Three weak, smooth or undulating keels, fine transverse wrinkles, but no peristomes. The cross section is tunnel-shaped. On each side of the tube base is a longitudinal cavity.
Remarks – In the palaeontological literature, the name ‘Serpula’ has often been used as an artificial conglomerate, meaning ‘a species of the family Serpulidae, genus unknown’. In neontological studies, however, Serpula has been shown to be a well-defined genus by its soft-part anatomy and operculum, but, unfortunately, the tube possesses no features that could characterise the genus. Therefore, it may be difficult to distinguish tubes of extinct species of Serpula from other genera and, therefore, each pre-Neogene Serpula can only be listed in open nomenclature.
Serpula? trilineata seems to be the correct name for tubes which formerly, but erroneously, were thought to belong to Janita (Jäger, 1983, 1987 [pl. 1, figs. 27, 28 only], 1988). Extant Janita has much stronger and more undulose keels.
Distribution – Gronsveld Member; Schiepersberg Member(?); Emael Member; Meerssen Member(?). The total known range is late Santonian to latest Maastrichtian.
Serpula? klaumanni Lommerzheim, 1979
Pl. 3, fig. 4.
Description – Small to medium sized; usually with a single narrow, low keel. The fine transverse ornament consists of sharp granules and short ledges, which are faintly curved anteriorly at the keel. Weak, short or, more often, long and bulge-shaped annular peristomes. The tube wall is thin and the base barely widened.
Distribution – Meerssen Member. The total known range is earliest Cenomanian and latest Maastrichtian.