Although not yet demonstrated to cause widespread mortality in current natural populations, Ostrea lurida is susceptible to infection by a small protistan
(Microsytos mack ini), recently present in commercial beds of Crassostrea gigas in British Columbia, Canada (Bower et al.
Petersen and Hansen (1960) were the first to describe new species of a group of protistans
known as heliozoa based on the electron microscopy of their scales.
A total of 22 scale-bearing protistans
was observed from 27 freshwater sites in the Gulf Coast States of Alabama, Mississippi, Louisiana and eastern Texas.
But all around them, in vastly greater numbers and variety, are invisible bacteria, protistans
, planktonic single-celled algae, aquatic fungi, and other microorganisms.
It is projected that in the coming years, we can expect to add some 8-- 100 million species of insects to the 950,000 species already recognized, another 100,000 protistans
to the 40,000 named species, and three times as many new mollusks as are currently known.
There is a highly diverse community of microorganisms living in the lesions of lobsters with ESD, including bacteria, protistans
, fungi, and nematodes (Chistoserdov et al.