Comparative x-ray microanalysis of the sporocyst wall of Aggregata octopiana and Aggregata eberthi (Protista: Apicomplexa)

Sporocyst walls of the coccidian parasites Aggregata eberthi and A. octopiana, were subjected to semiquantitative x-ray elemental microanalysis. Peaks above background level were obtained for Na, P, S and Si in both species, with also a peak for Ca in A. eberthi which was not detectable in A. octopiana. Whilst the amounts of Na, P and S can be considered similar for both species, the relative percentage of Si was 3 times higher in A. eberthi than in A. octopiana. This technique may be useful for distinguishing between the sporocysts of these two species.