Pterothecidae is an extinct family of Paleozoic molluscs of uncertain position, either Gastropoda or Monoplacophora, with isostrophically coiled shells.
Pterothecidae is an extinct family of Paleozoic molluscs of uncertain position, either Gastropoda or Monoplacophora, with isostrophically coiled shells. (en)
Pterothecidae is an extinct family of Paleozoic molluscs of uncertain position, either Gastropoda or Monoplacophora, with isostrophically coiled shells. (en)