Bivalvia - Cardiida - Ungulinidae
Alternative spelling: Microstagon
Parent taxon: Diplodonta according to E. V. Coan and P. Valentich-Scott 2012
See also Sepkoski 2002 and Todd 2001
Sister taxa: Diplodonta (Diplodonta), Diplodonta (Phlyctiderma), Diplodonta (Sphaerella), Diplodonta (Timothynus), Diplodonta (Zemysina), Diplodonta acclinis, Diplodonta aleutica, Diplodonta astartea, Diplodonta balcombensis, Diplodonta confusa, Diplodonta corbiscula, Diplodonta cornea, Diplodonta dalli, Diplodonta davisi, Diplodonta dilatata, Diplodonta dissona, Diplodonta ferruginata, Diplodonta globosa, Diplodonta hopkinsiensis, Diplodonta incerta, Diplodonta inconspicua, Diplodonta infrequens, Diplodonta lupinus, Diplodonta mediamericana, Diplodonta nucleiformis, Diplodonta orbella, Diplodonta paralta, Diplodonta parilis, Diplodonta problematica, Diplodonta punctata, Diplodonta shilohensis, Diplodonta soror, Diplodonta subquadrata, Diplodonta subrotunda, Diplodonta subrotundata, Diplodonta subvexa, Diplodonta torelli, Diplodonta transversaria, Diplodonta vaticani, Diplodonta villardeboeana, Diplodonta zelandica, Taras (Diplodonta) alta, Felaniella senegalensis, Diplodonta (Felaniella) sericata, Felaniella palmerae, Felaniella insula, Felaniella confusa, Felaniella (Felaniella), Felaniella (Zemysia) elliptica, Taras goodspeedi, Taras (Taras)
Subtaxa: Diplodonta (Microstagon) obliqua Microstagon miliaria
Distribution:
• Eocene of France (1 collection), the United Kingdom (1), United States (2: Alabama)
• Paleocene of Germany (1)
Total: 5 collections including 7 occurrences