This species infects the eggs of the
echiuroid worm (
Thalassema neptuni). This occurs while the eggs are within the genital pouches (nephridial sacs).
Schizogony and
sporogony both occur within the eggs. The mature sexual parasites are vermiform and immobile. The males are smaller than the females. The
microgametocyte, when it becomes spherical, gives rise to numerous, elongate
microgametes. These are similar to those of
Aggregata. The
oocysts have many
sporocysts, each with up to 12
sporozoites. The number of
chromosomes appears to be seven. ==References==