Some Environmental Boundaries of a Marine Ostracode

Individuals of the marine ostracode Hemicythere conradi Howe and McGuirt were acclimated in the laboratory at a salinity of 30 parts per thousand and water temperatures of 20-26 degrees C. They were able to survive salinities from 6 to 65 parts per thousand and water temperatures from 6 degrees to 36 degrees C. Individuals of this species also exhibited a positive response to light and preferred silty sand to coarser ooelitic sand when given free choice in laboratory experiments. The results are discussed in relation to the distribution of the species in the field.