Belotelson magister Fossil Mazon Creek Francis Creek Shale Carboniferous Illinois USA Genuine Specimen with Certificate of Authenticity

Description

Exquisite Belotelson magister Fossil from the Mazon Creek Beds, Illinois, USA

This remarkable specimen of Belotelson magister is an exceptional example from the world-famous Mazon Creek Fossil Beds of Illinois, USA, specifically from the Francis Creek Shale Member at Chowder Flats, near Morris. Dating to the Carboniferous Period (Pennsylvanian Subsystem, approximately 307 million years ago), this fossil represents one of the most beautifully preserved crustaceans from one of the world’s most important fossil lagerstätten. The Mazon Creek deposits are renowned for their soft-bodied preservation within ironstone concretions, capturing entire ecosystems in extraordinary detail.

The photograph shows a representative example of the fossil type, carefully chosen to reflect the quality and preservation typical of the actual specimen you will receive. The scale cube = 1cm, and full sizing details can be seen in the image.

Geological Context – The Francis Creek Shale and Mazon Creek Lagerstätte

The Francis Creek Shale, part of the Carbondale Formation, was deposited during the Pennsylvanian Stage of the Carboniferous Period in a coastal deltaic environment along the ancient tropical shoreline of the Illinois Basin. The area alternated between freshwater swamps, estuaries, and shallow marine conditions, creating ideal settings for the preservation of both terrestrial and marine organisms. Rapid burial by fine silts and clays, followed by mineral-rich groundwater infiltration, resulted in ironstone concretions that sealed and protected organic remains from decay.

The Mazon Creek Fossil Beds are celebrated globally for their exceptional three-dimensional preservation of soft-bodied fauna and flora. The fossils from this locality are so well-preserved that they provide rare insights into Carboniferous ecosystems — from ferns and horsetails to fish, amphibians, and delicate invertebrates like Belotelson magister.

Taxonomy and Morphological Features

Belotelson magister belongs to the class Malacostraca, order Belotelsonidea, and family Belotelsonidae, a group of extinct crustaceans closely related to modern shrimp and crayfish. It exhibits an elongated body divided into a cephalothorax and abdomen, terminating in a tail fan with well-defined telson and uropods. The segmented exoskeleton is thin but remarkably preserved in Mazon Creek concretions, often showing fine details such as carapace ridges, appendage impressions, and delicate pleurae.

These animals were likely nektonic or benthic scavengers, inhabiting shallow estuarine and coastal marine waters. Their morphology suggests agility in swimming and burrowing within soft sediment. Belotelson fossils are relatively uncommon compared to other Mazon Creek species, making them prized among collectors and palaeontologists alike for their scientific and aesthetic value.

Depositional Environment and Paleoecology

The depositional environment of the Francis Creek Shale was a deltaic estuary system bordered by dense coal-forming swamp forests. Seasonal flooding and sediment-laden waters created layered muds that encapsulated both terrestrial and aquatic life. Within these waters, Belotelson magister thrived among plants, fish, and early amphibians. The anoxic conditions at the seabed inhibited bacterial decay, allowing the mineralization process that led to fossil concretion formation. This unique preservation environment makes Mazon Creek one of the few fossil sites in the world where both hard and soft tissues are recorded in detail.

Scientific and Collectable Value

Specimens of Belotelson magister are of immense importance to paleontological research and are sought after by collectors due to their distinct anatomy and rarity. Each piece encapsulates over 300 million years of Earth’s history, revealing intricate biological structures within a concreted ironstone matrix. Fossils from the Mazon Creek Beds are highly valued not only for their scientific record but also for their natural beauty — each concretion splitting open to reveal a perfectly preserved window into an ancient world.

Authenticity and Provenance

All of our fossils are 100% genuine specimens and come with a Certificate of Authenticity, confirming verified provenance and geological context. This Belotelson magister fossil from the Francis Creek Shale, Mazon Creek, Illinois, is a fine example of Carboniferous crustacean preservation and a rare opportunity to own a specimen from one of the most significant fossil localities on Earth. Each piece has been professionally curated and represents a fascinating relic from the ancient tropical seas of the late Paleozoic era.