Utah cambrian grey shale rock with Choia carteri sponge embedded
close up of cambrian choia carteri sponge on grey shale rock
close up of grey shale rock showing embedded choia sponge
grey shale rock with visible choia sponge
Cambrian shale side view on black metal stand
Grey shale
Side view of shale rock on black metal stand
  • Load image into Gallery viewer, Utah cambrian grey shale rock with Choia carteri sponge embedded
  • Load image into Gallery viewer, close up of cambrian choia carteri sponge on grey shale rock
  • Load image into Gallery viewer, close up of grey shale rock showing embedded choia sponge
  • Load image into Gallery viewer, grey shale rock with visible choia sponge
  • Load image into Gallery viewer, Cambrian shale side view on black metal stand
  • Load image into Gallery viewer, Grey shale
  • Load image into Gallery viewer, Side view of shale rock on black metal stand

Utah Cambrian Choia carteri Sponge radiating spicules

Regular price
$125.00
Sale price
$125.00
Regular price
Sold out
Unit price
per 
Shipping calculated at checkout.

Very Rare and Excellently preserved fossilized Choia carteri sponge spicules in a radiating pattern. Found in the Wheeler shale Utah West Desert. Remnants of Utah Cambrian fossilized trilobite imprints present.

Age: Middle Cambrian (521 to 497 mya)

Species Name: Choia carteri 

Order / Family: Protomonaxonida / Choiidae

Phylum: Porifera

Locality: Millard County, Utah

Size: Approximately 8 1/2" x 6", 4.94 lbs.

Comes with metal stand.

The preserved skeletal spicules are not connected in most fossilized Cambrian sponges that are found. They are usually separated after death of the animal and the beginning of soft tissue decay. 

Characters of the sponge important for classification include skeletal composition and shape of skeletal spicules which are a small, needle-like anatomical structures that serve various functions... part of the skeleton, providing support and deterring predators, and are made of silica or calcium carbonate.

Sponges (Poriferans) are simple aquatic animals that attach to hard surfaces and feed and live by moving water through openings in the body wall. There are many forms of sponges varying in shape, size and if they are solitary or live in colonies. They exist in all water depths.

Choiidae is an extinct family of demosponges that lived from the Cambrian to the Lower Ordovician periods. These sponges somewhat resembled a pincushion, with siliceous spicules. They are known for their disc shape, covered with radiating spines, and are famous fossils from deposits found in Utah, Morocco, Canada and China.

Choia was originally thought to rest directly on the sea floor with radiating spines from the edge of it's flat, conical body and not attached to the seabed. Recently discovered fossils from Lower Ordovician Morocco show that the living animal was actually suspended high above the seafloor, attached via stalk-like spines derived from spicules.