Fossil Wiki by Fossils After Dark

Fossil Wiki

Welcome to Fossil Wiki — a growing collection of detailed overviews of trilobites and other invertebrates, drawn from decades of fieldwork, laboratory preparation and our own photography lab. Each entry combines scientific context with personal collecting notes, along with high-resolution photographs of the finest examples of species ever found.

Triarthrus eatoni trilobite in iconic lateral pose from Beecher’s Trilobite Bed showing pleural lobe compression, 1cm specimen

Triarthrus eatoni – Beecher’s Trilobite Bed

Nevadia weeksi trilobite

Nevadia weeksi


Beautifully preserved single Bristolia bristolensis trilobite specimen highlighting genal spines and exoskeleton detail, Pioche Formation

Bristolia bristolensis

Bristolia insolens trilobite showing genal spines and thoracic segments, one of the most iconic Early Cambrian trilobites from Nevada

Bristolia insolens


Olenellus chiefensis

Olenellus chiefensis

Olenellus gilberti

Olenellus gilberti


Olenellus fowleri

Olenellus fowleri

Olenellus terminatus

Olenellus terminatus


Olenellus nevadensis trilobite

Olenellus nevadensis

Nephrolenellus

Nephrolenellus geniculatus


A monstrous 17 cm Mesonacis fremonti-one of the finest examples ever found. Note the outstanding inflation and heavy mineralization of this specimen.

Mesonacis fremonti

Bolbolenellus

Bolbolenellus brevispina


Apex predator of the Cambrian

Anomalocaris – one of the earliest predators

An incredible 14cm example of Anomalocaris saron from the Lower Cambrian of Nevada. This specimen preserves exoskeleton surface detail and is 3D. Likely the finest example of a frontal appendage from the Lower Cambrian.

Lower Cambrian Olenellus species

Olenellus Wiki

Olenellus gilberti
Olenellus gilberti
Nephrolenellus
Nephrolenellus geniculatus