Family Rectonariidae Gr̹ndel, 1962

Remarks

A unique isolated valve of Rectonariidae was encountered in our material. Because most of this family is characterized by asymmetrically ornamented valves, it is kept in open nomenclature. It is, however, of pivotal importance since it is the youngest report of Rectonariidae, which were abundant in deepwater environments during the Devonian–Carboniferous (e.g., Gr̹ndel 1962) with a previously last documented occurrence in the Carnian, Late Triassic, of Turkey (Forel et al. 2019a).