Rare Bristolia brachyoma California Trilobite
Order Redlichiida, Family Olenellidae
Time: Uppermost Lower Cambrian
trilobite is 1 ¼” (3-cm) in length
Gold Ace Limestone, Carrara Formation, Mojave Desert, California
Bristolia brachyoma sits at the very top of the Gold Ace Limestone,
in California’s Mojave Desert. It is the last described
species of Bristolia to be discovered and described, and the
last of the lineage before the genus went extinct.
am aware of only two complete Bristolia brachyoma ever recovered.
is one of them. A highly respected amateur collector found
it over twenty-five years ago. At that time, the technical expertise
to prepare this positive/negative specimen did not exist. So, it
sat in a drawer these many years awaiting the amazing new fossil
preparation techniques of the last few years to evolve. I fortuitously
acquired this specimen last year, and only recently had it returned
from prep by one of USA’s premier trilobite preparators.
There has been some significant restoration done to the specimen.
(See the positive/negative photo of the specimen before preparation)
Some of the cephalic brim, upper cephalic portions and axial spine
were cast and reconstructed.
The preparation and reconstruction have proved to be a wise investment.
Being as highly prized by collectors as Bristolias are, this remarkably
rare, end of the lineage specimen will hopefully soon find a home
in an important Lower Cambrian trilobite collection, or museum.
fossil pictures to enlarge
before preparation below: