IDIOCOLPODA-PELOBIA GEN-N, SP-N, A NEW COLPODID CILIATE (PROTOZOA, CILIOPHORA) FROM AN EPHEMERAL STREAM IN HAWAII

Idiocolpoda pelobia gen. n., sp. n. was discovered in the mud of a dry river bed in Hawaii. Its morphology and infraciliature were studied in live cells using interference contrast optics and in specimens impregnated with silver carbonate and protargol. The new genus, Idiocolpoda, belongs to the family Colpodidae and is unique by having the oral apparatus located entirely at the left side of the body. The new species, I. pelobia, measures 25-40 x 15-30 mum and has a deep postoral groove which contains 2 specialized kinetics. The two lowermost preoral kinetics of the left side are distinctly shortened. The small oral apparatus is situated slightly above mid-body in the fight half of the left side of the cell. The flat vestibulum is conspicuously scrotum-shaped and unroofed, exposing the oral polykinetids, which are very similar to those known from small species of the genus Colpoda, on the surface of the cell. An improved key to the genera of the family Colpodidae is provided.