| Measurements | D mm | H/D | T/D | O/D | H/T |
|---|---|---|---|---|---|
| CP-88 | 41 | 0.52 | 0.28 | 0.17 | 1.87 |
| Jaffré 2022 p.83 | 41 | 0.51 | 0.28 | 0.15 | 1.83 |
| CP-583 | 47.9 | 0.52 | 0.27 | 0.19 | 1.93 |
| Holotype | 80 | 0.49 | 0.25 | 0.19 | 1.96 |
| CP-440 | 103 | 0.50 | 0.29 | 0.21 | 1.69 |
| Age | Origin |
|---|---|
|
Grey clay H. (I.) steinmanni zone Lower Albian |
Bully, Pays de Bray Seine-Maritime France |
Description. A fine specimen in phosphate covered with a pearly test and bearing a few pyrite crystals, with its body chamber on the last half-whorl. The whorls are very involute and compressed, with a high cross-section, with flat, barely divergent flanks up to the inner third, then slightly convex and converging towards a narrowly rounded venter. There is thus a peri-umbilical flattening, clearly visible in oblique light. The narrow umbilicus has a subvertical low wall and an angular margin. The test is smooth, except for fine, falcate growth lines, starting very proversely and effaced on venter.
Remarks. The juveniles are smooth but often, from 50 mm onwards, develop proverse falciform constrictions on the internal mold, corresponding to fine ribs on the test. However, our specimen still has a smooth test at 103 mm. The species is found in the Lower Albian, from the tardefurcata zone to the steinmanni zone, in Europe and Transcaspia. It is abundant from the floridum zone to the subhilli zone, in the Aube region and at Folkestone, but large specimens are rare and no fully adult specimens are known. Newton and Jukes-Brown (1900) called it Beudanticeras ligatum but without illustrating it or designating a reference specimen. As in our specimen, B. (B.) newtoni can exhibit a periumbilical flattening, which is also found in the closest species, B. (B.) revoili (see its entry). Without this flattening, it closely resembles B. (B.) laevigatum. The latter (see also its entry) is distinguished by its simpler sutures and a staggered vertical extension, from the bulliensis zone to the benettianus zone. The two species were long confused with B. (B.) beudanti (see its entry), but the latter is more recent (cristatum and pricei zones, Upper Albian).