Pagetia
Encyclopedia
Pagetia is a genus of trilobite
s known from the Middle Cambrian Burgess Shale
. Its remains are sometimes found in the otherwise-empty tubes of the polychaete worm Selkirkia
. Its major characteristics are a small size of less than one centimeter, eyes, two thoracic segments, an annulated pygidium
, and a terminal axial spine.
Trilobite
Trilobites 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 , and they flourished throughout the lower Paleozoic era before...
s known from the Middle Cambrian Burgess Shale
Burgess Shale
The Burgess Shale Formation, located in the Canadian Rockies of British Columbia, is one of the world's most celebrated fossil fields, and the best of its kind. It is famous for the exceptional preservation of the soft parts of its fossils...
. Its remains are sometimes found in the otherwise-empty tubes of the polychaete worm Selkirkia
Selkirkia
Selkirkia is a genus of predatory priapulid worm known from the Middle Cambrian Burgess Shale. In the Burgess Shale, 20% of the tapering, organic-walled tubes are preserved with the worm inside them, whereas the other 80% are empty...
. Its major characteristics are a small size of less than one centimeter, eyes, two thoracic segments, an annulated pygidium
Pygidium
The pygidium is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. It contains the anus and, in females, the ovipositor...
, and a terminal axial spine.