Uninucleate and multinucleate stages of a protozoan parasite are described from cultured abalone @entity1539 Martyn, 1784 in New Zealand. The parasite is identified as a haplosporidian by the occurrence of multinucleate plasmodia, mitochondria with tubular cristae, lipid droplets, anastomosing endoplasmic reticulum (aER), multivesicular bodies (MVBs), haplosporogenesis by the production of haplosporosome-like bodies from nuclear membrane-bound Golgi, and their maturation to haplosporosomes. @entity558 occurred in the plasma membrane and coated vesicles were scattered in the cytoplasm, particularly in association with the Golgi face away from the nucleus, and aER. It is concluded that the outward face of the Golgi may be the trans face, and that aER is the trans-Golgi network. @entity558 and bristle-coated vesicles are reported from a haplosporidian for the first time. The vesicles in the MVBs resembled the cores and inner membranes of haplosporosomes, without the outer layer. The possible inter-relationships of these features are discussed. The abalone parasite differs from previously described haplosporidians in the apparent absence of a persistent mitotic spindle, and the presence of intracytoplasmic coccoid to rod-shaped bacteria resembling Rickettsiales-like prokaryotes. Phylogenetic analysis of the 16S rRNA gene sequence of the Rickettsiales-like prokaryotes indicated that these organisms belong to the @entity39340 cluster. The prokaryotes have a high (7%) sequence divergence from known Rickettsieae, with @entity39340 sp. and @entity39340 being the closest relatives. The lack of non-molecular evidence prevents us from proposing a new rickettsial genus at this time.

Ultrastructure of a haplosporidian containing Rickettsiae, associated with mortalities among cultured paua XXXX .

@entity558 :: ('MESH:C536528', 'Disease') :: ['Coated pits'] @entity39340 :: ('35791', 'Species') :: ['R. massiliae', 'Rickettsia'] @entity1539 :: ('MESH:D007499', 'Disease') :: ['Haliotis iris']
@entity1539 :: (MESH:D007499,Disease) :: ['Haliotis iris']
