Eopachydiscus brazoense Ammonite Fossil Texas USA with COA

Description

Genuine Eopachydiscus brazoense Ammonite Fossil

This genuine ammonite fossil is identified as Eopachydiscus brazoense and comes from Grayson County in Texas, USA. It is preserved from the Duck Creek Formation and dates to the Albian Stage of the Lower Cretaceous. The photographs show the actual carefully chosen fossil offered for sale, so the ammonite pictured is the exact specimen you will receive.

Albian Lower Cretaceous Age

The Albian is the final stage of the Early Cretaceous Period, spanning approximately 113 to 100.5 million years ago. During this interval, broad marine waters covered significant areas of what is now Texas. These seas formed part of the developing Western Interior marine system and supported ammonites, bivalves, gastropods, echinoids, fish, and other organisms.

After death, an ammonite shell could settle on the sea floor and become buried by mud or carbonate-rich sediment. Compaction, mineral replacement, and later geological change preserved the shell or internal mould as a fossil. The documented Albian age gives this specimen a clear position near the end of the Lower Cretaceous.

Eopachydiscus brazoense

Eopachydiscus was an extinct marine cephalopod with a coiled shell divided internally into chambers. The living animal occupied the final body chamber, while earlier sealed chambers assisted with buoyancy control. Ammonites were relatives of modern squid, cuttlefish, and nautiluses, although they formed their own diverse and now extinct group.

Eopachydiscus is recognised for a robust, generally inflated shell form that could develop strong ribs and nodes as the animal grew. Whorl proportions, umbilical width, ribbing, tubercles, and the form of the outer edge help palaeontologists compare related species. Examine the photographs for the coiled whorls, shell outline, ornament, umbilical region, natural matrix, and preserved surface details visible on this individual Eopachydiscus brazoense.

Scientific and Stratigraphic Interest

Ammonites evolved relatively rapidly and were widely distributed through ancient oceans. Their changing shell forms make them valuable index fossils, allowing geologists to correlate sedimentary rocks and establish relative ages. Albian ammonites from Texas are important for interpreting marine connections, sea-level changes, and faunal development during the later Early Cretaceous.

An ammonite shell grew by adding progressively larger chambers around the outer whorl. Internal septa met the shell wall along complex suture lines, reinforcing the chambered structure. External ribs and tubercles also contributed to shell strength and recorded changes in growth.

Duck Creek Formation Geology

The Duck Creek Formation is a well-known Lower Cretaceous marine rock unit in north-central Texas. Its limestones and marls formed beneath an ancient sea and preserve a varied fossil assemblage. Ammonites from the formation are especially valued because they combine attractive natural preservation with clear stratigraphic context.

A specimen from a named formation carries useful geological information beyond a general age. It can complement a collection arranged by North American formation, geological stage, ammonite genus, US state, or ancient marine environment.

Grayson County Texas Provenance

Grayson County lies near the Texas-Oklahoma border and includes important exposures of Lower Cretaceous rocks. Fossils from this area document the marine conditions that affected the southern central United States during the Albian. A precise county provenance adds collecting and educational value to this specimen.

Natural Fossil Character

Natural colour, mineral texture, small breaks, areas of wear, and variations in preservation reflect the fossil’s long geological history. These are expected features of an authentic specimen rather than manufacturing defects. Every ammonite preserves a different balance of shell material, mineral replacement, internal mould, and surrounding rock, giving each piece unique character.

The multiple photographs show this exact Eopachydiscus brazoense from useful angles. They allow close inspection of its condition, ornament, outline, matrix, proportions, and display qualities. Full sizing is shown in the photographs, which provide the clearest scale information for this individual fossil. The images are not stock photographs and do not represent a similar specimen.

Certificate of Authenticity

This genuine fossil includes a generic Certificate of Authenticity card with a lifetime guarantee. Its Albian age, Duck Creek Formation context, Grayson County provenance, and robust ammonite form make it a distinctive addition to a fossil cabinet, study collection, office display, or educational setting. It is also a thoughtful gift for anyone interested in Texas fossils, Lower Cretaceous geology, ammonite evolution, palaeontology, or genuine natural history specimens.