Trilobite

Object/Artifact

-

Crater Rock Museum

Name/Title

Trilobite

Entry/Object ID

2011.57.69

Description

Description: Phylum: Arthropoda Class: Trilobita Family: Proetoidea Genus: Proetida Species: dechenella lucasensis Common Name: Trilobite Age: Cambrian to Ordovician Location: Utah Description: Large, very finely detailed complete fossil covering entire specimen. Matrix is light and dark gray. The fossil is a rusty brown with some lighter patches. Physical Characteristics: Trilobites ( /'tra?l?ba?t/, /'tr?l?ba?t/; meaning "three lobes") are a well-known fossil group of extinct marine arthropods that form the class Trilobita. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period (526 million years ago), and they flourished throughout the lower Paleozoic era before beginning a drawn-out decline to extinction when, during the Devonian, almost all trilobite orders, with the sole exception of Proetida, died out. Trilobites finally disappeared in the mass extinction at the end of the Permian about 250 million years ago. The trilobites were among the most successful of all early animals, roaming the oceans for over 270 million years.[2]When trilobites first appeared in the fossil record they were already highly diverse and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton an extensive fossil record was left, with some 17,000 known species spanning Paleozoic time. The study of these fossils has facilitated important contributions to biostratigraphy, paleontology, evolutionary biology and plate tectonics. Trilobites are often placed within the arthropod subphylum Schizoramia within the superclass Arachnomorpha (equivalent to the Arachnata),[3] although several alternative taxonomies are found in the literature.Trilobites had many life styles; some moved over the sea-bed as predators, scavengers or filter feeders and some swam, feeding on plankton. Most life styles expected of modern marine arthropods are seen in trilobites, with the possible exception of parasitism (where there is still scientific debate).[4] Some trilobites (particularly the family Olenidae) are even thought to have evolved a symbiotic relationship with sulfur-eating bacteria from which they derived food.[5] Family: Proetoidea Genus: Proetida Kingdom: Animalia (Animals) Class: Trilobita Phylum: Arthropoda

Collection

Museum Collection of Fossils

Acquisition

Accession

2011.57

Source or Donor

Museum Collection of Fossils

Acquisition Method

Long-term Loan

Dimensions

Width

8-11/16 in

Depth

1-3/4 in

Length

10 in

Location

Location

Container

Left

Drawer

Back Row / Bottom

Shelf

Right

Cabinet

Case # 51

Wall

North

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent