Gonyaulax monilata cysts were found in the sediments from 13 of 37 stations sampled in the Indian River, Florida. The distribution of cysts appears to be the result of 2 unrelated phenomena. In areas where blooms have occurred in the past, the lack of circulation in the lagoon allows the cysts to accumulate. South of Turkey Creek, cysts are found associated with shellfish beds where no blooms have been reported. It is suggested these cysts have been introduced into shellfish regions with oysters which are annually rafted from areas where G. monilata blooms occur. Blooms of this toxic dinoflagellate can be expected to reoccur in regions they have in the past, and the possibility of blooms in the vicinity of the shellfish beds around Grant, Florida now exists. However, there is not sufficient evidence to implicate direct toxicity to shellfish by G. monilata.
Owen, Kevin C. and Norris, Dean R., "Benthic Resting Cysts Of Gonyaulax Monilata Howell And Their Relationship To Red Tides In The Indian River, Florida" (1982). Ocean Engineering and Marine Sciences Faculty Publications. 110.