Cockroaches, Germany (Schiffmann, 1919: probably used the oriental cockroach); Venezuela (Tejera, 1926).
Organism usually found in the intestinal tract of cockroaches where it is attached to the gut cells. Cysts are passed in the feces. Occasionally, G. blattarum (fig. 2, J) is found in the body cavity (Leidy, 1853a; Hall, 1907). Though this is considered to be one of the commonest of the Sporozoa encountered in cockroaches, DeCoursey and Otto (1956) found only 10 of 217 P. americana and B. germanica, collected in restaurants in Egypt, infested with this species. Watson (1917) found a dozen or more in one specimen of Blatta orientalis. Zasukhin (1929, 1930) found 2.6 percent of 3,000 oriental cockroaches infected with this parasite.
Gregarina fastidiosa Harrison
Natural host.—Aptera fusca, South Africa (Harrison, 1955): All mature females were heavily infected; in all specimens there were over 100 parasites in the gut. All nymphs were infected, the earlier instars more lightly than the later instars. Gregarines were found in all parts of the gut except the crop and gizzard.
Gregarina gibbsi Harrison
Natural host.—Temnopteryx phalerata, South Africa (Harrison, 1955): Although the cockroaches were found in groups, only 32 percent were infected and only 10 percent heavily. The gregarines were found in the anterior mesenteron but none in the hepatic caeca. All cysts were found in the hind gut or rectum.
Gregarina illinensis M. E. Watson
Natural host.—Parcoblatta pensylvanica, U.S.A., Illinois (Watson, 1915, 1916): The intestine of one cockroach was found to contain 25 of these gregarines.