Pulmissa

Pulmissa is a genus of extinct brachiopods that lived during the Early Ordovician to Late Silurian periods. The name Pulmissa is derived from the Greek words 'poulos,' meaning many, and'missa,' meaning mixture or mixture of.

Fossilized Pulmissa shells have been found in various regions around the world, including North Africa, Eastern Europe, and Australia. The shells of Pulmissa brachiopods were relatively small, ranging in size from 1 to 3 centimeters in length, and exhibited a distinctive discoidal shape with a gently sloping dorsal valve.

Pulmissa was a diverse genus, with multiple species identified through fossil records. Research suggests that Pulmissa species were primarily filter feeders, using their brachial cavity to strain small phytoplankton and detritus from the surrounding water. The genus is also notable for its relatively rapid evolution, with new species emerging over short geological timescales.

Geologists have used Pulmissa fossils as important biostratigraphic markers in determining the age and correlation of Ordovician and Silurian rock units. Pulmissa fossils are relatively common in sedimentary sequences of this age, making them valuable indicators of paleoecological and paleoiminal conditions.