Original description: [Cylindrical, the apex rounded and rather 225 narrower; the segments (10, including the frontal one) very slightly constricted, narrow, flat, with approximately 11 - 12 conspicuous (opposite), parallel longitudinal lines in each segment. Length 125 µ, maximum breadth 49 µ. (Translated from Latin by E.M.R. and W.R.R.)]
Biogeography and Palaeobiology
Similar speciesacephala Geographic distribution Paleobiology Phylogenetic relations
Geological Range: Last occurrence (top): within Paleogene Period (23.03-66.04Ma, top in Chattian stage). Data source: Lazarus et al. 2015 - "P age group" First occurrence (base): within Paleogene Period (23.03-66.04Ma, base in Danian stage). Data source: Lazarus et al. 2015 - "P age group"
Plot of occurrence data:
Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes