Two molts occur within the egg during development of the larva. The first molt occurs outside the host resulting in the formation of an infective resting stage. The second molt occurs inside the cockroach (Todd, 1941, 1944).
Transmission of the nematode is direct, eggs in the resting embryonated stage being infective (Dobrovolny and Ackert, 1934).
Hoffman (1953) described a filamentous bacterium, Streptomyces leidynematis Hoffman, which grows on the cuticle of L. appendiculata in P. americana. Leidy (1853) noted the presence of simple, inarticulate, amorphous filaments, growing from nematodes infecting B. orientalis. Bütschli (1871) and Magalhães (1900) described similar filaments adhering to the surface of oxyurids from cockroaches.
Leidynema appendiculata (Leidy, 1850) Chitwood, 1932?
Natural host.—Eurycotis floridana, U.S.A., Massachusetts (Roth and Willis, unpublished data, 1955): Determined by Dr. G. Steiner who wrote us, "In Eurycotis floridana there were ten specimens of the nematode Leidynema appendiculata (Leidy, 1850). This cockroach is obviously a new host for this nematode. I am not sure that the nematode exactly agrees with the description as given in the literature."
Leidynema cranifera Chitwood, 1932
Natural hosts.—Blaberus craniifer, U.S.A., Florida (Chitwood, 1932); Massachusetts (Roth and Willis, unpublished data, 1955). Determined by Dr. G. Steiner.
Blaberus atropos?, U.S.A., Florida (Chitwood, 1932): B. craniifer has generally been recorded as B. atropos of Stoll which is a closely related but distinct South American species (Rehn and Hebard, 1927).