Diagnosis | Micrasterine spatangoids with:
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Range | Eocene to Recent; worldwide. |
Remarks | Amongst the various taxa previously grouped as Brissidae are a small number of taxa with a longitudinally elongate labral plate and short petals. In true Brissidae the labral plate is short and wide and never extends further back than half-way along the first ambulacral plate. These probably represent a clade but are currently left in open nomeclature.
One other taxon, Protobrissus Lambert, 1907, from the late Palaeocene of France may also belong here but is so poorly known that t is omitted from the following key. |