umbilicated cowrie (Umbilia hesitata)
umbilicated murex (Muricopsis umbilicatus)
umbilicated sand-snail (Eunaticina umbilicata)
umbilicated top-shell (Herpetopoma vixumbilicata)
umbonella tellin (Cyclotellina umbonella)
uncertain margin-shell (Cystiscus incertus)
undesirable sundial-shell (Solatisonax injussa)
unmarked false-creeper (Seila insignis)
unusual lepton (Mysella anomala)
unwoven pyramid-shell (Odostomia deplexa)
upcurved emozamia (Emozamia licinus)