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MARINE MOLLUSCS AS HOSTS FOR SYMBIOSES
C. Subphylum SPOROZOA
Class Telosporea
The sporozoan class Telosporea includes several species which are
known to parasitize commercially important marine molluscs. These
parasites belong to the genera Nematopsis, Porospora, Pseudoklossia
and Hyaloklossia.
1. Nematopsis ostrearum Prytherch, 1938. (Figs. 29 and 30)
(Subclass Gregarinia; order Eugregarinia; suborder Cephalina; family
Nematopsis ostrearum was first described by Prytherch in 1938.
Later (Prytherch, 1940), he redescribed this parasite and reported its
life cycle. This gregarine is found in the tissues of moribund and dead
oysters, Crassostrea virginica, along the Atlantic coast of the United
Porosporidae)
FIG. 29. Nematopsis ostrearum spores in labial palp of Crassostrea virginica. Upper
two spores are located within phagocytes.
States, extending from Mobjack Bay, Virginia, to Lake Barre and
vicinity in Louisiana. Prytherch, as the result of experimental infection
experiments, has reported that :
fatal effects of N . ostrearum were demonstrated and depended upon the
intensity of the infection, the age and general condition of the host, and the