Fast Facts about Asaphiscus wheeleri
Name:
Asaphiscus wheeleri. The genus name Asaphiscus is tied to the family Asaphiscidae, while wheeleri refers to the Wheeler Formation / Wheeler Shale where these trilobites are commonly found.
Taxonomy:
Phylum Arthropoda; Class Trilobita; Order Ptychopariida; Family Asaphiscidae; Genus Asaphiscus.
Common species:
Asaphiscus wheeleri and Asaphiscus laeviceps. A. wheeleri is the familiar Wheeler Shale species often collected in Utah.
Age:
Middle Cambrian.
Distribution:
North America, especially Cambrian exposures in Utah and Nevada. The best-known collecting areas are in the House Range of western Utah.
Body size:
Most complete Asaphiscus specimens are about 1 to 2 inches long. Large examples can reach about 2.5 inches, while exceptional specimens may approach 3 inches.
Diet:
Likely a particle feeder or deposit feeder that moved along the Cambrian sea floor and consumed organic material in the sediment.
Appearance:
Asaphiscus is a plain, oval-shaped trilobite with a rounded cephalon and pygidium. It lacks the dramatic spines and ornamentation seen in many other trilobites, but complete specimens are attractive and collectible.
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Asaphiscus wheeleri Trilobite Facts and Identification
Asaphiscus wheeleri is one of the better-known Cambrian trilobites from the Wheeler Shale of Utah. It is not as flashy as spiny trilobites, but it is an important and recognizable Wheeler Shale fossil. Its smooth, oval outline, rounded head shield, simple body form, and thin exoskeleton make it a classic example of a Middle Cambrian trilobite from the House Range.
Unlike many trilobites that are known mostly from fragments, Asaphiscus specimens can sometimes be found complete. However, many fossils are missing the free cheeks, which likely separated during molting. Complete examples with all major body parts preserved are more desirable to collectors, especially when the trilobite is well centered on the shale slab.
The average Asaphiscus specimen is about 1 to 2 inches long. Larger individuals around 2.5 inches are impressive, and complete specimens close to 3 inches are exceptional. Because the exoskeleton can be thin and delicate, careful preparation is often needed to expose the fossil without damaging the shell.
Where to Find Asaphiscus wheeleri Trilobite Fossils
Asaphiscus wheeleri fossils are mainly found in Cambrian Wheeler Shale deposits of Utah and Nevada. In Utah, the classic collecting region is the House Range near Delta, where Asaphiscus occurs alongside the famous Elrathia kingii trilobite.
One of the easiest public places to look for Wheeler Shale trilobites is the U-Dig quarry near Delta, Utah. Collectors there commonly find Elrathia, while Asaphiscus specimens may also occur in the same general Cambrian shale layers.
For a collecting example from the area, see my Utah trilobite fossil hunting trip in the Wheeler Shale near Delta, Utah.
Recommended Trilobite and Fossil Hunting Books:
The Trilobite Collector's Guide
Andy Secher, 2024
This book by Andy Secher, a leading trilobite collector, offers a captivating journey into the world of these ancient arthropods. With over 400 stunning photos, entertaining top-ten lists, invaluable collecting tips, and ways to spot a fake trilobite, it's a must-have for fossil enthusiasts!
Trilobites: Common Trilobites of North America (A NatureGuide Book)
Jasper Burns, 2000
An excellent guide for identifying North American trilobites, featuring meticulous line drawings and concise information on classification, geologic range, and distribution. Ideal for enthusiasts seeking detailed insights and accurate identification of these ancient arthropods.
101 American Fossil Sites You've Gotta See
Albert B Dickas, 2018
This is a great updated fossil sites book with at least one fossil site in each state. Each site is broken into 2 pages. One has detailed information, such as directions, GPS coordinates, formation information, etc...
The other is dedicated to images of the site and the fossils found there. It also gives information on fossil 'viewing' sites such as dinosaur trackways, museums, and active excavations.
Plus, my fossil photos are peppered throughout this book!
