Hawaiian Phoronida (Lophophorata) and Their Distribution in the Pacific Region

Abstract

Five Phoronis species are found in Hawaiian waters. Three were recorded previously, and two others, P. muelleri and P. pallida, are added here. Phoronis ovalis (the smallest) and P. hippocrepia are perforant species forming burrows in coral rock, shells, and barnacle encrustations, and P. psammophila, P. muelleri, and P. pallida are sand-dwellers. Species diagnosis in phoronids requires sectioning to estimate muscle formulas and arrangement of other internal organs. Included are a key to Hawaiian species based on visible external features (so not entirely accurate), description of each, and distribution in Hawaiian waters and the Pacific Ocean.