On the rugose area and caudal papillae distribution in Dirofilaria immitis(Leidy, 1856) Railliet & Henry, 1911, by scanning electron microscopy

The objective of this study was to obtain a better characterization of Diro filaria immitis (Leidy, 1856) Railliet & Henry, 1911, in Brazil, ratifying previous accounts and adding new data on the rugose area on the ventral sur face of the spiralled posterior portion of males observed by scanning elect ron microscopy, which presents a different arrangement compared to other sp ecies of the genus, and differs also from the genera Litomosoides Chandler, 1931, and Wuchereria Silva Araujo, 1877, adding another taxonomic characte r to Dirofilariinae and Onchocercinae. Scanning electron microscopy studies also showed some aspects of the distribution of caudal papillae in D. immi tis that have not been described before.