Are the Protozoan Faunae of Termites Specific?

Abstract

The species of the lower families of termites, so far investigated, have each a characteristic hindgut fauna of flagellate Protozoa, belonging to the orders Hypermstigida and Polymastigida. All individuals of a given termite species over wide geographic ranges present, so far as known, a similar grouping of species. This raises the question whether we are dealing here with specific protozoan faunae, whose species are able to exist only in the one specific termite host, with which they have established obligatory physico-chemical relations, or whether the faunae are distinct because of the isolated habit of life of the termite colony.

A colony of Porotermes froggatti received in normal condition, but which an examination of nearly 100 intestines showed to have lost its protozoan fauna, supposedly due to conditions encountered in transit, was used. Various methods were resorted to in attempts to refaunate the Porotermes individuals with the Protozoa from species belonging to other genera of termites.

All attempts to accomplish this by keeping Porotermes individuals in close association with Termopsis augusticollis, Neotermes malatensis and Reticulitermes hesperus proved failures.

Feeding defaunate Porotermes individuals with the intestinal contents of the 3 species named failed to accomplish transfaunation in most cases. In a few instances Protozoa survived for a few days, polymastigotes in all cases. No signs of increase of numbers or permanent establishment were noted.

All attempts to infect Porotermes indlividuals by applying to the anal aperture a drop of intestinal content of the infective species were failures.

Finally resort was had to injection by pipette through the anal aperture. For these experiments Termopsis was used as the source of infective material. Several cases of persistence for several hours and even a few days were observed, and finally with the last individual what seemed to be successful transfaunation was obtained.