| Measurements | D mm | H/D | T/D | O/D | H/T |
|---|---|---|---|---|---|
| 5/785 Saveliev | 50 | 0.48 | 0.31 | 0.21 | 1.55 |
| Holotype Casey (half-whorl) | 70 | 0.46 | 0.31 | -- | 1.48 |
| 224 Destombes S. daguini | 86 | 0.45 | 0.32 | 0.23 | 1.41 |
| CP-444 | 87 | 0.47 | 0.33 | 0.18 | 1.41 |
| Age | Origin |
|---|---|
|
S. vnigri zone, S. caperata subzone in Mangystau. C. floridum zone in England and France. Lower Albian |
North-Aktau Ridge Mangystau Peninsula Kazakhstan |
Description. Phragmocone without test, compressed and very involute, with visible sutures. Trapezoidal whorl section with a narrow, slightly flattened venter. Shallow umbilicus with low wall. The last whorl, overlapping the previous one by 70%, shows 14 elongated umbilical bullae (some attenuated), oblique on the umbilical wall and then giving rise to pairs of sigmoid ribs. There are 41 ribs on the last whorl, including 13 unforked, which become very blunt with growth. They are higher and more widely spaced on venter, where they form a proverse sinus at 90°. Some intercalary ribs originate very high on the flanks. The 1st lateral lobe is long and almost symmetrical. A piece of test preserved on the other side shows that the ribs were stronger on the shell. Conforms to the Russian description by Saveliev (1973).
Remarks. A rare species from England and Transcaspia. According to Casey (1965), the ventral elevation of the ribs distinguishes it from Cleoniceras quercifolium and jeanneli, and the venter is not flattened enough for a Pseudosonneratia. Sonneratia (E.) strigosa Saveliev, 1973, and, according to Owen (1988, p. 193), Sonneratia daguini Destombes in Rat (1979) are junior synonyms. We have added specimen 224 from Destombes to the table. Compared to the closest species S. (E.) rotula (see its entry), caperata has a narrower venter, more but less prominent ribs, a more pinched ventral sinus, and a more symmetrical first lateral lobe. Sonneratia parenti Jacob, 1907, has the same proportions but a well-rounded venter, a deeper umbilicus, ribs that weaken later, and more pronounced bullae.