Tubercles, spines and sensory receptors are the most studied structures of
adult male worms of Schistosoma mansoni isolated in other countries. The
purpose of this investigation was to properly define these structures in
Brazilian worms. Specimens 7-8 weeks after infection were recovered from
albino SW mice and from a wild rodent (Nectomys squamipes) and processed
for scanning electron microscopy studies. Photomicrographs of the anterior
region with the aspects related to the outer and inner regions of both
suckers were considered. The ventral portion of the middle region was
represented by the anterior of gynaecophoric canal while the dorsal surface
was studied in its ventral and dorsal regions mainly focusing the aspect of
the tubercles, spines and sensorial papillae. The outer surface of the oral
sucker is spiny and spines are bigger, sharp with sensory receptors in
their posterior edge. Tubercles with spines or receptors are more
concentrated in the middle region and in one of the margins of the
gynaecophoric canal. An excretory pore-like structure in the posterior
portion was observed. The gynaecophoric canal has few sensory structures,
spines broadned in their mid-region and are sharp pointed at the distal
end. It was concluded that the presently studied characters are similar to
those previously reported.