Immunological and ultrastructural characterization of spirotrichonymphid flagellates from Reticulitermes grassei and R. flavipes (syn. R. santonensis), with special reference to Spirotrichonympha, Spironympha and Microjoenia

Five species of spirotrichonymphids representing three genera have been studied by light and immunofluorescence microscopy, and by transmission electron microscopy. The genus Spirotrichonympha, represented by S. flagellata from Reticulitermes grassei, is characterized by a compound axostyle composed of several fibers or subaxostyles. The genus Spironympha, represented by S. kofoidi from Reticulitermes flavipes (syn. R. santonensis) and by the two new species S. verticis and S. lanceata, is characterized by flagellar lines restricted to the anterior area and a simple, tubular axostyle. Spironympha verticis and S. lanceata are mainly distinguished by ultrastructural details of their flagellar lines and axostyle. These three Spironympha species were found in hosts identified as R. flavipes or R. santonensis, but not in R. grassei. This provides additional support for the synonymy of R. santonensis with R. flavipes recently demonstrated by molecular methods. The generic diagnosis of Microjoenia is emended, based on an ultrastructure study of M. fallax.