Chapter 8 Cambrian, Ordovician and Silurian non-stromatoporoid Porifera
Lucy A. Muir
Joseph P. Botting
Marcelo G. Carrera
Matilde Beresi
10.6084/m9.figshare.3453479.v1
https://geolsoc.figshare.com/articles/dataset/Chapter_8_Cambrian_Ordovician_and_Silurian_non-stromatoporoid_Porifera/3453479
<p>The Cambrian, Ordovician and Silurian distributions of non-stromatoporoid sponges are reviewed. The earliest Cambrian faunas
contain mostly hexactinellids, with protomonaxonids dominating middle Cambrian assemblages. There are no obvious palaeobiogeographical
patterns, with many genera being found widely. Vauxiids, lithistids and heteractinids are apparently confined to low latitudes,
but this may be due to a poor fossil record. Most known Ordovician faunas are from low latitudes, although some high-latitude
faunas are known, which contain reticulosan hexactinellids and protomonaxonids. There is some division of faunas within Laurentia,
into eastern and western provinces, with the western assemblage extending across low northern latitudes during the Late Ordovician.
During the Silurian Period, sponge diversity was very low during the Llandovery Epoch, probably partly owing to lack of habitat
for taxa restricted to carbonate facies, and also because of sampling bias. There was a dramatic increase in diversity through
the Silurian Period, mostly owing to an apparent diversification in the demosponges; however, there are many ghost lineages,
indicating that their fossil record is poorly known. Non-lithistid sponges are very poorly known, with few recorded outside
Euramerica. The currently available data for Early Palaeozoic sponges are too incomplete to allow any reliable palaeobiogeographical
inferences.
</p>
2016-06-21 11:27:26
protomonaxonid
Ordovician
palaeobiogeographical
latitude
Chapter 8 Cambrian
middle Cambrian assemblages
diversity
Silurian Period
hexactinellid
fauna
Geology