Myxobolidae Explained

Myxobolidae is a family of myxosporean parasites which typically infect freshwater fishes, and includes the economically significant species, Myxobolus cerebralis. They have been shown to have a complex life cycle, involving an alternate stage in an invertebrate, typically an annelid or polychaete worm.

Morphology

Myxosporean spores of genera belonging to the Myxobolidae are flattened parallel to the sutural line. They typically contain two polar capsules, and have a central vacuole in which they store β-glycogen. In some genera, the spore walls are drawn out into long processes which are thought to slow sinking through the water column.

Actinosporean stages which have been linked to members of the Myxobolidae have a single central "style" and three processes or "tails", around 200 micrometers long, projecting from this. A sporoplasm packet at the end of the style contains 64 germ cells surrounded by a cellular envelope. There are also three polar capsules, each of which contains a coiled polar filament.

Genera

• Dicauda Hoffman & Walker, 1978^[1]
• Hennegoides Lom, Tonguthai & Dyková, 1991^[2]
• Henneguya Thélohan, 1892
• Laterocaudata Chen & Hsieh, 1984^[3]
• Myxobolus Bütschli, 1882^[4]
• Thelohanellus Kudo, 1933^[5]
• Trigonosporus Hoshina, 1952^[6]
• Unicauda Davis, 1944^[7]

Notes and References

1. Hoffman . G. L. . Walker . R. . October 1978 . A new myxosporidan, Dicauda atherinodi n.g., n. sp. of the minnow, Notropis atherinoides Rafinesque . . en . 1 . 4 . 343–349 . 10.1111/j.1365-2761.1978.tb00038.x . 0140-7775.
2. Lorn . J . Tonguthai . K . Dykova . I . 1991 . Hennegoides longitudinalis n. gen. n. sp.,a myxosporean parasite of Osphronemus gourami from Thailand . Diseases of Aquatic Organisms . en . 11 . 143–145 . 10.3354/dao011143 . 0177-5103.
3. Web site: IRMNG - Laterocaudata Chen & Hsieh, 1984 . www.irmng.org . 10 May 2021.
4. Book: Bütschli, O. . Dr. H. G. Bronn's Klassen und Ordnungen des Thier-Reichs, wissenschaftlich dargestellt in Wort und Bild. Erster Band. Protozoa . 1882 . C. F. Winter'sche Verlagshandlung . Bütschli . O. . Leipzig . de . Myxosporidia . https://archive.org/details/drhgbronnsklasse0101bron/page/590/mode/2up.
5. Kudo . R. . July 1933 . A Taxonomic Consideration of Myxosporidia . . 52 . 3 . 195–216 . 10.2307/3222254.
6. Hoshina. T. . 1952. Notes on some myxosporidian parasites on fishes of Japan. Journal of the Tokyo University of Fisheries. 39. 1. 69–89.
7. Davis . H. S. . October 1944 . A Revision of the Genus Henneguya (Myxosporidia) with Descriptions of Two New Species . Transactions of the American Microscopical Society . 63 . 4 . 311–320 . 10.2307/3223303.