Wonderful Early Silurian Life

Sci-News has a story about interesting new fossils from Wisconsin.  The Waukesha Biota, a Silurian lagerstatten located near Milwaukee, dates to about 437 million years ago.  The deposit preserves an ancient tidal lagoon.  The fossils are found in a fine-grained mudstone known as the Brandon Bridge Formation.   The locality and its fauna are described in a paper in the journal Geology Today.

Microbial mats (cyanobacteria), algae, sponges, conulariids (possibly related to jellyfish), graptolites, worms (polychaetes and palaeoscolecids), an orthocone nautiloid, a rare conodont animal (only the second complete example of this lamprey-like animal in the world) and a lobopodian also occur.

A dozen types of trilobites, including some new species, and crustaceans (phyllocarids and ostracodes) are quite common.

The exceptional preservation of the fossils was helped by the tidal conditions and/or microbial mats.

Soft tissues (limbs, eyes and guts) are preserved in some of the arthropods, lobopodian and conodont.

Leave a Reply

Discover more from Earth Science Club of Northern Illinois

Subscribe now to keep reading and get access to the full archive.

Continue reading