depurinoi

Depurinoi is a genus of small, bivalved marine organisms that were first described in the early 21st century from sedimentary deposits in the Triassic Marne–Sologne Basin of France. The name derives from the Latin *de* (down) and *pur* (clean), reflecting the organisms’ apparent capacity for filtering and biodegradation of organic particles, a function supported by their unique exoskeletal morphology.

Taxonomically, Depurinoi has been placed within the phylum Nanozoara, class Protoholozoea, order Bivalvedia. The genus comprises three species, D. mirabilis, D. robusta and D. velaria, which differ in shell size, hinge structure and inner lamina thickness. Shells are typically 1–2 mm in length, composed of iron‑rich calcite, giving them a distinctive reddish hue in fossil sections. The ventral opening is adapted for a specialized gullet that filters planktonic organisms and detritus, implying an ecological role as a primary decomposer in Early Triassic marine ecosystems.

Depurinoi fossils are predominantly found in fine-grained limestone and shale strata of the Early Triassic, suggesting a preference for calm, low‑energy shelf environments. Some recent sedimentary evidence from central Italy indicates that Depurinoi may have survived into the early Jurassic, though this remains contested. Current paleontological research focuses on their bioinclusion potential in reconstructing paleo‑oxygenation events. High‑resolution synchrotron imaging has begun to reveal internal microarchitecture, offering insights into the evolution of filtration mechanisms among early metazoans.

In summary, Depurinoi represents a distinct group of small, bivalved filter‑feeding organisms that contribute valuable information to studies of Early Triassic marine life and the evolutionary pathways of filter mechanisms in early metazoans.