Combing the shores of Oval Beach in Saugatuck, Michigan, or any beach along the fresh water coastline, you will find lots of these interesting fossil samples of one of Earth’s earliest creatures!
They are often called lace corals because of their delicately threaded appearance, but they are not true corals; instead, they are bryozoans, moss like animals. There are still varieties living today most commonly in marine water environments. They form tight colonies sculptured by hard, limy, branching structures. The colony consists of thousands of individual animals called “zooids”. Each individual zooid lives inside its own limy tube called a zooecium. The zooecium are the size of sewing needles.
The sample above was discovered on the shores of Lake Michigan in Berrien County, Michigan.
A single zooid begins the colony. A bryozoan colony has been observed growing from a single zooid to 38,000 in just five months. Each additional zooid is a clone of the very first one. Their fossil record dates back 500 mya with 15,000 known species. Today there are about 3,500 living species.
INTERESTING HOW THEY FEED Each zooid has an opening through which the animal can extend its ring of tentacles called lophophores in order to feed. It captures microscopic animals from the water as they pass by its lophophores. If one zooid receives food it nourishes the neighboring zooids because they are joined by strands of protoplasm. If people could only be more like them, feeding the masses; imagine!
Common Name: “Lace Coral”
Scientific Name: “Fenestella, plebeian”
Phylum: Bryozoa (means moss animal)
Class: Stenolaemata (means tubular walls)
Family: Fenestellida (group of fan shaped or mesh-like bryozoans)