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Cryptolithus Triolobites
The Lace Collar Trilobite

Beautiful cryptolithus trilobite fossil, showing the lace collar. Fossils found at Swatara Gap, Pennsylvania

Fast Facts about the Cryptolithus Trilobites

Cryptolithus trilobite fossils from Swatara Gap, Pennsylvania.

Name: Cryptolithus (pronunciation: "crypto - lithus") - In Latin, Crypto means "hidden" and Lithus means "stone". Cryptolithus translates into "Hidden Stone".

Common Name: "Lace Collar" Trilobite:
The little pits, or fenestrae on the priphery of the cephalon used for filter feeding look like miniature lace collars.

Taxonomy: Phylum: Arthropoda - Class: Trilobita - Order: Asaphida - Superfamily: Trinucleioidea - Family: Trinucleidae - Genus: Cryptolithus

Species: C. Bellulus and C. Tessellatus

Age: Ordovician

Distribution: North America

Body Size:
Cryptolithus are small trilobites. They are usually less than one inch in length (25 mm).

Filter Feeder

Physical Appearance:
The cephalon of cryptoluthus is wide and contains main small holes. These holes were used for filter feeding. Cryptolithus also have very long genial spines. The spines are longer than the trilobite.

Cryptolithus Trilobite Facts and Information - The Details

Cryptolithus tessellatus trilobite restoration of appendages, showing the soft body parts that rarely preserve. This is figure 20 from Raymond, 1920 p.64. - ' A restoration of the appendages drawn by Doctor Elvira Wood from the original specimens and from the photographs made by Professor Beecher. x9 '

Cryptolithus trilobites are a genus of small (less than an inch), blind, trilobites from the Ordovician. They are often called "Lace Collar" Trilobites, because of the little pits, or fenestrae on the priphery of the cephalon. These pits can easily be seen in the images above. The pits were actuall holes, The trilobite would stir up sediment and filter it through these holes. It was thus a filter feeder, feeding on debris near the bottom of the sea floor.

Lace collar trilobites, besides for the lace-like cephalon, are also known for their very long genial spines. These spines are actually longer than the trilobite, from cephalon to pygidium.

Although they are a very small genus of trilobite, they are incredibly beautiful. Unfortunately, most of the time they are found as fragments. However, some Ordovician formations were preserved in just the right conditions to leave these trilobites intact. One such formation is the Martinsburg Formation. This formation was exposed in the famous Swatara Gap, in Lebanon County, PA. This formation left casts of the trilobites coated in a fine rust colored powder called limonite. Limonite is a type of iron oxide, specifically, it's an iron oxide-hydroxide powder.

Where to find Cryptolithus Trilobite Fossils

Cryptolithus can be found in the upper Ordovician formations in North America.

The world famous specimens of C. bellulus come from the Martinsburg Formation. A famouse collecting locality for this formation was the Swatara Gap locality in Lebanon County, Pennsylvania. Here, the fossils, including complete Cryptolithus, are coated with a beautiful rusty iron-oxide powder. Cryptolithus tessellatus are common in the Kope Formation. The Kope formation is an extensive upper Ordovician formation that runs through Kentucky, Indiana, and Ohio. Unfortunately, whole Cryptolithus trilobites are rare in this formation, although fragments can be abundant

Cryptolithus fragments in a Kope Formation 'hash plate'

The above and below images show 'hash plate' sections from the Kope Formation. It is composed almost entirely of crinoid fragments, some brachiopods, bryozoans, and Cryptolithus trilobite fragments.

Kope formation Matrix - Crinoids and Cryptolithus fragments.

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!

Trilobites for Sale:

Trilobites from Fossil Era
Trilobite fossils are some of the most beautiful and collectible fossils in the world! They make beautiful display and conversation pieces, and can be very affordable gifts for fossil and paleontology enthusiasts. Fossil Era has a huge selection of top quality trilobites from many states and many countries. It's fun just to browse through the inventory and look at all the different types!

Cryptolithus Fossil Examples

Cryptolithus Bellulus from Swatara Gap

This is a beautiful cryptolithus preserved in iron-oxide power. Notice the lace collar, and long genial spines.

Formation: Martinsburg Formation
Age: Upper Ordovician
Location: Swatara Gap, Lebanon Co., PA

This is a nother complete cryptolithus trilobite fossil. The lace collar is not very visible at this angle.

Formation: Martinsburg Formation
Age:Upper Ordovician
Location: Swatara Gap, Lebanon Co., PA

This is a cephalon of a cryptolithus

Formation: Martinsburg Formation
Age:Upper Ordovician
Location: Swatara Gap, Lebanon Co., PA

Cryptolithus tessellatus from the Kope Formation

This is part of a 'hash plate' from the Kope Formation. It shows numerous Crinoid fragments, as well as pieces of bryozoan, brachiopods, and Cryptolithus tessellatus trilobites.

Formation: Kope Formation
Age: Ordovician
Location: Ohio

References / Works Cited

Raymond, Percy Edward (1920). The Appendages, Anatomy, and Relationships of Trilobites. Connecticut Academy of Arts and Sciences - Yale University Press. Released Ebook from Project Gutenberg - Produced by Thomas Cosmas - 2012. Ebook Here.

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