Description
Rare Barremian Ammonite Association from France
This rare and genuine fossil specimen contains a fragment identified as Kutatissites sp., labelled in association with Gassendiceras, together with Pseudocrioceras coquandi. It originates from Alpes-de-Haute-Provence in south-eastern France and dates from the Barremian Stage of the Lower Cretaceous.
The occurrence of two identifiable ammonite forms within one specimen gives this piece additional palaeontological and display interest. Rather than representing a single isolated shell, it preserves evidence of the varied cephalopod fauna that inhabited the ancient marine basin covering this part of France during the Early Cretaceous.
The abbreviation “sp.” indicates that the Kutatissites fragment has been identified confidently to genus level but has not been assigned to a particular species. Its fragmentary condition is an authentic feature of preservation and reflects the natural processes of shell breakage, seabed deposition, burial and fossilisation.
This carefully chosen fossil is the exact specimen shown in the listing photographs. Full sizing and scale information can be seen in the photographs.
Kutatissites and Gassendiceras Fragment
Kutatissites is an extinct ammonite genus recognised from Lower Cretaceous marine deposits. The preserved portion in this specimen represents part of a once much larger chambered shell. Even where an ammonite is incomplete, features such as whorl curvature, shell expansion, ribbing, tubercles and the shape of the preserved cross-section can provide important information for identification.
The reference to Gassendiceras reflects comparison or association with another characteristically ornamented Barremian ammonite genus. Gassendiceras is especially associated with Upper Barremian deposits of south-eastern France and is known for shells bearing strong ribs and prominent ornamentation.
As the ammonite grew, new shell material was added around the aperture. The shell was divided internally by curved partitions called septa, creating a series of chambers. Only the final chamber housed the living animal; the earlier chambers formed a buoyancy system connected by a narrow tube known as the siphuncle.
On a fragmentary specimen, portions of the chamber walls, shell ornament or sediment-filled interior may remain visible. These preserved structures provide a fascinating cross-section through the construction of an ammonite shell.
Pseudocrioceras coquandi Heteromorph Ammonite
The associated Pseudocrioceras coquandi belongs to a distinctive group of heteromorph ammonites. Heteromorph ammonites departed from the tightly overlapping spiral familiar from many traditional ammonite fossils. Their shells could be openly coiled, hooked, helical or partly uncoiled.
Pseudocrioceras developed an open, crioconic spiral in which successive whorls remained separated or only loosely connected. This produced a broad central opening and left the earlier growth stages visible. The shell commonly displayed pronounced transverse ribs, with stronger ornament occurring at intervals.
The species Pseudocrioceras coquandi was named in honour of the French geologist and palaeontologist Henri Coquand. Its distinctive morphology and restricted occurrence make it an important component of latest Barremian ammonite assemblages in south-eastern France.
Shell curvature, rib arrangement, whorl proportions and changes in ornament through growth are among the features used to recognise these unusual ammonites. Depending on preservation, this specimen may retain external shell detail, a natural internal mould or a combination of both.
Barremian Lower Cretaceous Geology
The Barremian is a stage of the Lower Cretaceous positioned between the Hauterivian and Aptian stages. It represents an interval approximately 129 to 121 million years ago, although numerical dates may be refined as the geological timescale is updated.
The stage takes its name from Barrême in Alpes-de-Haute-Provence, making fossils from this region especially significant to the history of Cretaceous geology. The marine sedimentary successions of south-eastern France have been studied extensively because they preserve diverse and rapidly changing ammonite assemblages.
Ammonites are valuable index fossils because many species evolved quickly, became geographically widespread and existed for relatively limited periods. Their occurrence enables palaeontologists to divide sedimentary sequences into detailed zones and subzones and to correlate rocks exposed at different localities.
Pseudocrioceras coquandi is associated with a distinctive latest Barremian fossil interval close to the Barremian–Aptian transition. Its presence gives this specimen meaningful biostratigraphic context in addition to its visual and collecting appeal.
Ancient Tethyan Marine Environment
During the Barremian, the region now forming Alpes-de-Haute-Provence lay beneath a marine basin connected to the ancient Tethys Ocean. Fine carbonate mud and clay accumulated on the seabed, eventually forming the layered limestones and marls now exposed throughout the mountains and valleys of south-eastern France.
These waters supported a diverse ecosystem containing conventionally coiled ammonites, heteromorph ammonites, belemnites, nautiloids, bivalves, gastropods, brachiopods, echinoids, crustaceans, fish and marine reptiles.
The ammonites represented in this specimen would have lived in the water column above the seabed. Their chambered shells provided buoyancy, while the living animals extended their heads, eyes and arms from the final body chambers. They were cephalopod molluscs and therefore distant relatives of modern squid, cuttlefish, octopuses and nautiluses.
Changing sea levels, sediment supply, water circulation and oxygen conditions produced repeated variations in the sedimentary record. These geological changes helped create the richly fossiliferous Lower Cretaceous deposits for which the region is internationally recognised.
Natural Association and Fossilisation
After death, the ammonite shells descended to the seabed, where currents, scavengers and sediment movement could break or redistribute them. This explains why fragmentary ammonite remains are a natural and scientifically informative part of many marine fossil assemblages.
The shells were gradually covered by fine sediment. Soft tissues decomposed, while mud entered the empty chambers and accumulated around the remains. Continued burial compacted the sediment and transformed it into rock.
The ammonites’ original aragonitic shells could subsequently dissolve, recrystallise or be replaced by other minerals. Sediment hardened within the chambers to form internal moulds, while surviving shell surfaces preserved elements of the original ribs and ornamentation.
Any fractures, incomplete areas, matrix, mineral markings, weathered surfaces or variations in colour are genuine consequences of this long geological process. The association of the Kutatissites fragment and Pseudocrioceras coquandi preserves a small natural record of the Barremian marine community rather than an artificially assembled decorative item.
Alpes-de-Haute-Provence Provenance
Alpes-de-Haute-Provence is one of Europe’s classic regions for Lower Cretaceous geology and ammonite palaeontology. Its deeply eroded alpine landscapes expose extensive sequences of marine limestone and marl ranging through several Cretaceous stages.
The department includes historically important geological localities that have contributed to the definition, study and correlation of Barremian strata. Fossils from this region are sought after for their scientific provenance, diverse species and connection to the development of European stratigraphy.
A specimen retaining its fossil identifications, geological stage and regional locality provides substantially greater context than an ammonite sold without collection information. This example is particularly notable for combining two different ammonite elements in one fossil-bearing piece.
Actual Fossil and Certificate of Authenticity
This is a genuine fossil specimen and not a cast, replica or artificial reproduction. The listing photographs show the exact Kutatissites sp. fragment with Pseudocrioceras coquandi ammonites that will be supplied. The images allow its natural preservation, shell ornamentation, matrix, colour and individual geological features to be examined before purchase.
Full sizing is provided in the photographs.
The specimen includes a generic Certificate of Authenticity card carrying a lifetime guarantee. Its rare ammonite association, unusual heteromorph component, Barremian age and documented Alpes-de-Haute-Provence provenance make it an excellent addition to a specialist ammonite collection, Lower Cretaceous display, educational geological collection or natural-history cabinet.
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