Reteporella sp.

Reteporella sp.

Reteporella sp. Bryozoa of order Cheliostomatida from the marine Eocene in the valley of Marfà (Castellcir, Moianès).

Bryozoa are a large group of colonial animals living on the seabed that can easily be mixed up with corals or sponges. Bryozoa expanded along Paleozoic era, but at the end of the Permian period large groups of Bryozoa became extinct. The order Cheilostomatida appeared later, during the Late Cretaceous, and it is still the largest group of Bryozoa today. There are more species of Bryozoa from the fossil record than living species.

Cheilostomatida colonies have a calcareous skeleton. Reteporella grimaldii living on the Catalan coast seabed until 50 meters depth and known as Venus’ lace, helps understanding Reteporella fossils from the marine Eocene of the districts of Bages and Moianès. Colonies of Reteporella grimaldii span about 10 cm in diameter; they are made of a calcareous skeleton of orange wavy sheets as potato chips though perforated like a sieve, arranged like the petals of a garden rose or a gelatinous fungus of the genus Tremella, and rooted to the substrate by its base. Zooids that feed on phytoplankton by filtration are integrated into these sheets.

[photo Florenci Vallès and Jordi Badia]