mesnilium mesnilium mesnilium is a genus of parasitic alveolates belonging to the phylum apicomplexia. its vertebrate hosts are fish. the vectors are not presently known but are thought likely to be leeches. mesnilium scientific classification domain: eukaryota clade: diaphoretickes clade: tsar clade: sar clade: alveolata phylum: apicomplexa class: aconoidasida order: haemospororida family: plasmodiidae genus: mesniliummisra, haldar and chakravarty, 1972 species: m. malariae binomial name mesnilium malariaemisra, haldar & chakravarty, 1972 taxonomy the genus was created in 1972 by misra, haldar and chakravarty. description merogony occurs in erythrocytes and reticulo-endothelial cells. gamogony occurs only in erythrocytes and pigment granules are present only in microgamonts and macrogametes. hosts the only known host of this parasite is the freshwater murrel (ophicephalus punctatus).