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Pirania auraeum

The Protomonaxonida are a heterogeneous group of primitive fossil sponges usually included in the desmosponjas. However, they have also occasionally been linked to the order Reticulosa, a group of hexactinellid affinities, so their relationships are critical to understanding the origins of today's various classes of sponges. Sponges are among the earliest recognizable animals in the fossil record . Although there is general agreement that they were one of the first groups of animals to evolve, the relationship of sponges to other animals is uncertain: we do not yet know if the first animal was a sponge or if they are specialized organisms that evolved from an animal previous. Understanding the early evolution of fossil sponges is critical to resolving these uncertainties, but although living sponges are easily divided into four distinct classes, early fossil sponges are often ambiguous. An important group of early fossil sponges are the protomonaxonids, which are generally considered early examples of demosponges (the ruling living class).

Era: Paleozoic

Period: Lower Ordovician

Stage: Floian (477.7 - 470.0 Ma)

Location: Djbel Bou Zéroual, Region of Drâa-Tafilalet, Zagora Province , Morocco

Coordinates: 30 ° 33'10.9 "N 5 ° 57'14.8" W

Description: Fezouata formation or shale Fezouata contains extraordinary fossil because the animals were buried quickly deposits storm formed by silts and clays, favorable conditions for the storage of soft tissue (now pyritized or altered due to a mixture of oxides and iron hydroxides, hence its orange-red color)

The fossils belong to two intervals, Tremadocian and Floian, much less rich in fossils.


Source consulted:


Fossil well preserved, 100% natural, without restoration or painting.

Matrix measurements: 10 x 6 x 1.8cm / 3.94 "x 2.36" x 0.71 "

Sponge size: 1.7 cm / 0.67 "

Weight: 187 gr / 0.41 lb


This piece will travel insured in a safety package to arrive in perfect condition.

Pirania auraeum (Protomonaxonida)

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