†family Steinmanellidae Cooper 1991 (clam)
Bivalvia - Trigoniida - Steinmanellidae
Parent taxon: Myophorelloidea according to M. R. Cooper and H. A. Leanza 2017
Sister taxa: Frenguelliellidae, Megatrigonioidae, Myophorelloidae
Subtaxa: Yaadiinae
Ecology: facultatively mobile infaunal suspension feeder
Distribution:
• Cretaceous of Japan (6 collections), Mexico (1), Peru (4), the United Kingdom (10), United States (59: California, Oregon)
Total: 80 collections including 82 occurrences