Verticordia (Trigonulina) hancocki F. R. Bernard, 1969
Verticordia hancocki F. R. Bernard, 1969
Verticordia novemcostata (A. Adams & Reeve, 1850)
Trigonulina novemcostata is a carnivorousbivalve in the familyVerticordiidae.[1] It is native to the South China Sea with 7–8 prominent ribs on its surface[2] and ranges from about 0.7-5 millimeters in size[3] in accordance with the unaccepted genusHippagus it was originally described as. It is the only currently known species in the genus Trigonulina that lives outside of the western Atlantic Ocean,[4] being found in the South China Sea[1] and Pacific Ocean. This species has been observed between California and Peru[5] as well as in Costa Rica.[6]Malacologists currently debate if T. novemcostata is a separate species or a variant of T. ornata due to their similar appearances and habitat overlap.[5]