sedimentary

Flexicalymene Trilobite Fossil

Flexicalymene meeki (Order Phacopida, Family Calymenidae)

AI-generated identification · may be incorrect

Commonly preserved in limestone or shale; Hardness: 3-4 (calcite replacement); Color: Earthy grays, browns, and ochre; Structure: Distinctive three-lobed body division (cephalon, thorax, pygidium); Luster: Dull to earthy; Often found in a 'rolled' or enrolled defensive position.

Hardness: 3-4 (calcite replacement)
Color: Earthy grays, browns, and ochre
Luster: Dull to earthy

Identified March 23, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through permineralization in marine sedimentary environments during the Late Ordovician period (approximately 450 million years ago); notably part of the Cincinnati Arch formation.

Uses & applications

Primarily used for educational purposes, scientific research, and as highly collectible paleontological specimens for hobbyists and museums.

Geological facts

Flexicalymene is one of the most famous trilobite genera because they often enrolled into a ball for protection, much like modern pill bugs. They are the official state fossils of Ohio.

Field identification & locations

Identify by looking for rhythmic segmented ridges (thoracic segments) and a distinct central axial lobe; commonly found in the tri-state area of Ohio, Kentucky, and Indiana. Collectors should look for nodules in creek beds or road cuts containing limestone and shale layers.